JP5785736B2 - Hydrogen production apparatus and hydrogen production method - Google Patents

Description

  The present invention relates to a hydrogen production apparatus and a hydrogen production method.

  In recent years, the use of renewable energy has been desired from the viewpoint of depletion of fossil fuel resources and the suppression of global warming gas emissions. There are a wide variety of renewable energy sources such as sunlight, hydropower, wind power, geothermal power, tidal power, and biomass. Among them, sunlight has a large amount of available energy, and there are geographical restrictions on other renewable energy sources. Because of the relatively small amount, early development and popularization of technology that can efficiently use energy from sunlight is desired.

  Possible forms of energy generated from sunlight include electrical energy produced using solar cells and solar thermal turbines, thermal energy by collecting solar energy in a heat medium, and other types of sunlight. Examples include storable fuel energy such as liquid fuel and hydrogen by substance reduction. Many solar cell technologies and solar heat utilization technologies have already been put into practical use, but the energy utilization efficiency is still low, and the cost of producing electricity and heat is still high. Technology development is underway. Furthermore, while these forms of electricity and heat can be used to supplement short-term energy fluctuations, it is extremely difficult to supplement long-term fluctuations such as seasonal fluctuations, It is a problem that there is a possibility that the operating rate of the power generation equipment may be reduced due to the increase in power generation. On the other hand, storing energy as a substance, such as liquid fuel and hydrogen, is extremely effective as a technology that efficiently supplements long-term fluctuations and increases the operating rate of power generation facilities. It is an indispensable technology to raise and reduce carbon dioxide emissions thoroughly.

  The types of fuel that can be stored are roughly divided into liquid fuels such as hydrocarbons, gaseous fuels such as biogas and hydrogen, solid pellets such as biomass-derived wood pellets and metals reduced by sunlight. it can. In terms of ease of infrastructure development and energy density, liquid fuel, gaseous fuel including hydrogen in terms of total utilization efficiency improvement with fuel cells, etc., solid fuel in terms of storability and energy density, Although each form has advantages and disadvantages, a hydrogen production technique by decomposing water with sunlight has attracted particular attention from the viewpoint that water that can be easily obtained as a raw material can be used.

As a method of producing hydrogen using solar energy using water as a raw material, platinum is supported on a photocatalyst such as titanium oxide, and this substance is put in water to perform light separation in a semiconductor, and an electrolytic solution. The water is decomposed directly at high temperature using the photolysis method by reducing protons and oxidizing water, or by using thermal energy such as a high-temperature gas furnace, or indirectly by coupling with redox of metals, etc. Pyrolysis method that uses the metabolism of microorganisms that use light such as algae, water electrolysis method that combines electricity generated by solar cells and water electrolysis hydrogen production equipment, photoelectric conversion used in solar cells Examples of the method include a photovoltaic method in which electrons and holes obtained by photoelectric conversion are used in a reaction by a hydrogen generation catalyst and an oxygen generation catalyst by supporting a hydrogen generation catalyst and an oxygen generation catalyst on the material. Among these, the one that has the possibility of producing a small hydrogen production device by integrating the photoelectric conversion unit and the hydrogen generation unit is considered to be a photolysis method, a biological method, a photovoltaic method, From the viewpoint of the conversion efficiency of solar energy, the photovoltaic method is considered to be one of the technologies closest to practical use.
So far, a hydrogen production apparatus in which photoelectric conversion and hydrogen generation are integrated has been disclosed (for example, Patent Document 1). By using such a hydrogen production apparatus, solar energy can be efficiently stored as hydrogen.

Japanese Patent No. 4559438

However, a conventional hydrogen production apparatus using solar energy requires a large installation area in order to use as much solar energy as possible. In addition, since conventional hydrogen production equipment is generally fixedly installed, the installation location can be used for other purposes even at night when sunlight cannot be received or when the installation location is to be used temporarily for other purposes. Can not.
This invention is made | formed in view of such a situation, and provides the hydrogen production apparatus which can utilize an installation place effectively.

  The present invention is a hydrogen production apparatus that is deformable from the first form to the second form or from the second form to the first form, comprising at least one hydrogen production module provided in a deformable manner, wherein the hydrogen production The module includes a photoelectric conversion unit having a light receiving surface and a back surface, and a first electrolysis electrode and a second electrolysis electrode provided on the back surface side of the photoelectric conversion unit, and the first and second electrolysis electrodes are: When light enters the light receiving surface of the photoelectric conversion unit and the first and second electrolysis electrodes come into contact with the electrolytic solution, the electrolytic solution is electrolyzed using electromotive force generated by the photoelectric conversion unit receiving light. The first gas and the second gas are provided so as to be able to generate the first gas and the second gas, respectively, and one of the first gas and the second gas is hydrogen and the other is oxygen. Abbreviation of the light receiving surface included The body is a form capable of directly receiving sunlight, and the second form is included in the same or different hydrogen production module on the light receiving surface side or the back surface side of the photoelectric conversion unit included in one hydrogen production module. Provided is a hydrogen production apparatus characterized in that the photoelectric conversion unit is located.

According to the present invention, the first and second electrolysis electrodes are configured to electrolyze the electrolytic solution using the electromotive force generated by the light received by the photoelectric conversion unit to generate the first gas and the second gas, respectively. Since it is provided, the first gas can be generated on the surface of the first electrolysis electrode, and the second gas can be generated on the surface of the second electrolysis electrode. Moreover, since one of the first gas and the second gas is hydrogen, hydrogen can be produced.
According to the present invention, since the first electrolysis electrode and the second electrolysis electrode are provided on the back side of the photoelectric conversion unit, light can be incident on the light receiving surface of the photoelectric conversion unit without using the electrolyte solution. It is possible to prevent absorption of incident light and scattering of incident light. As a result, the amount of incident light to the photoelectric conversion unit can be increased, and the light use efficiency can be increased.
According to the present invention, since the first electrolysis electrode and the second electrolysis electrode are provided on the back surface side of the photoelectric conversion unit, light incident on the light receiving surface is generated from the first and second electrolysis electrodes, respectively. It is not absorbed or scattered by the first gas and the second gas. As a result, the amount of light incident on the photoelectric conversion unit can be increased, and the light utilization efficiency can be increased.

  According to the present invention, from the first mode in which substantially the entire light receiving surface included in the hydrogen production apparatus can directly receive sunlight, the light receiving surface side of the photoelectric conversion unit included in one hydrogen production module or It is possible to transform the hydrogen production apparatus into the second form in which the photoelectric conversion unit included in the same or different hydrogen production module is located on the back side, and transform the hydrogen production apparatus from the second form to the first form Therefore, by setting the hydrogen production apparatus to the first configuration when there is solar radiation, the amount of light incident on the light receiving surface of the photoelectric conversion unit can be increased and hydrogen can be produced efficiently, and there is no solar radiation. By setting the hydrogen production apparatus to the second form when it is desired to use the installation place of the hydrogen production apparatus for other purposes, the hydrogen production apparatus can be made compact and the installation area can be reduced. Since the hydrogen production apparatus can be made compact, the vacant space can be used for other purposes, and the installation location of the hydrogen production apparatus can be used effectively. In addition, since the hydrogen production apparatus can be made compact, the hydrogen production apparatus can be easily accommodated, and the installation location of the hydrogen production apparatus can be easily changed. In addition, when a hydrogen production apparatus is installed in a cold region, it is considered that the hydrogen production apparatus may be damaged due to freezing of the electrolyte. It becomes possible to protect the manufacturing apparatus from cold. Similarly, the hydrogen production apparatus can be easily protected when there is a risk of damage to the hydrogen production apparatus, such as during high temperatures or strong winds. Furthermore, when the hydrogen production apparatus of the present invention is used as a water electrolysis apparatus using external electric power, hydrogen generated by using the compact second embodiment can be efficiently recovered.

It is a schematic plan view in the 1st form of the hydrogen production apparatus of one Embodiment of this invention. (A) is a schematic plan view in the 2nd form of the hydrogen production apparatus of one Embodiment of this invention, (b) is the schematic side view. It is a schematic plan view of the hydrogen production module contained in the hydrogen production apparatus of one embodiment of the present invention. It is a schematic sectional drawing of the hydrogen production module in dotted line AA of FIG. It is a schematic back view of the hydrogen production module contained in the hydrogen production apparatus of one embodiment of the present invention. It is a schematic plan view in the 1st form of the hydrogen production apparatus of one Embodiment of this invention. It is a schematic top view in the 1st form of the hydrogen production apparatus of one embodiment of the present invention. It is a schematic plan view in the 1st form of the hydrogen production apparatus of one Embodiment of this invention. (A) is a schematic plan view in the 2nd form of the hydrogen production apparatus of one Embodiment of this invention, (b) is the schematic side view. It is a schematic plan view in the 1st form of the hydrogen production apparatus of one Embodiment of this invention. (A) is a schematic side view in the 2nd form of the hydrogen production apparatus of one Embodiment of this invention, (b) is the schematic top view. It is a schematic back view of the hydrogen production module contained in the hydrogen production apparatus of one embodiment of the present invention. It is a schematic sectional drawing of the hydrogen production module contained in the hydrogen production apparatus of one Embodiment of this invention. It is a schematic sectional drawing of the hydrogen production module contained in the hydrogen production apparatus of one Embodiment of this invention. It is a schematic sectional drawing of the hydrogen production module contained in the hydrogen production apparatus of one Embodiment of this invention. It is a schematic sectional drawing of the hydrogen production module contained in the hydrogen production apparatus of one Embodiment of this invention. It is a schematic sectional drawing of the hydrogen production module contained in the hydrogen production apparatus of one Embodiment of this invention. It is a schematic sectional drawing of the hydrogen production module contained in the hydrogen production apparatus of one Embodiment of this invention. It is a schematic sectional drawing of the hydrogen production module contained in the hydrogen production apparatus of one Embodiment of this invention. It is a schematic sectional drawing of the hydrogen production module contained in the hydrogen production apparatus of one Embodiment of this invention. It is a schematic circuit diagram of the hydrogen production apparatus of one Embodiment of this invention. It is a schematic circuit diagram of the hydrogen production apparatus of one Embodiment of this invention. It is a schematic circuit diagram of the hydrogen production apparatus of one Embodiment of this invention. It is a schematic circuit diagram of the hydrogen production apparatus of one Embodiment of this invention.

  The hydrogen production apparatus of the present invention is a hydrogen production apparatus that can be transformed from the first form to the second form or from the second form to the first form, and includes at least one hydrogen production module that is deformably provided. The hydrogen production module includes a photoelectric conversion unit having a light receiving surface and a back surface, and a first electrolysis electrode and a second electrolysis electrode provided on the back surface side of the photoelectric conversion unit, and the first and second electrolysis The electrode for electrolyte uses an electromotive force generated by light received by the photoelectric conversion unit when light enters the light receiving surface of the photoelectric conversion unit and the first and second electrolysis electrodes come into contact with the electrolyte. The first gas and the second gas are provided so that the first gas and the second gas can be generated, respectively, one of which is hydrogen and the other is oxygen. Included in hydrogen production equipment The substantially entire light receiving surface is a form capable of directly receiving sunlight, and the second form is the same or different on the light receiving surface side or the back surface side of the photoelectric conversion unit included in one hydrogen production module. The photoelectric conversion unit included in the manufacturing module is positioned.

In the hydrogen production apparatus of the present invention, there are a plurality of the hydrogen production modules, and the first mode is a mode in which the hydrogen production modules are arranged so that sunlight can enter the light receiving surface of the photoelectric conversion unit of each hydrogen production module. The second form is preferably a form in which the hydrogen production modules are stacked.
According to such a configuration, when the hydrogen production apparatus is in the first form, the amount of light incident on the photoelectric conversion unit of each hydrogen production module can be increased, and when the hydrogen production apparatus is in the second form, The manufacturing apparatus can be made compact and the installation area can be reduced.
In the hydrogen production apparatus of the present invention, it is preferable that the hydrogen production apparatus further includes a connecting portion that connects a plurality of hydrogen production modules.
According to such a structure, a some hydrogen production module can be connected by a connection part, and the form of a hydrogen production apparatus can be changed by changing arrangement | positioning of a some hydrogen production module.

In the hydrogen production apparatus of the present invention, it is preferable that the connecting portion has a structure including a rotating shaft.
According to such a structure, a connection part becomes rotatable with a rotating shaft, and each hydrogen production module can be made movable. Thus, the hydrogen production apparatus can be transformed from the first form to the second form or from the second form to the first form.
In the hydrogen production apparatus of the present invention, it is preferable that the connecting portion has a guide groove, and at least one hydrogen production module slides along the guide groove.
According to such a configuration, the hydrogen production module can be changed from the first form to the second form or from the second form to the first form by sliding the hydrogen production module along the guide groove. .

In the hydrogen production apparatus of the present invention, it is preferable that the respective hydrogen production modules are separable, and are connected by the first connection part in the first form and are connected by the second connection part in the second form.
According to such a configuration, the hydrogen production apparatus can be in the first configuration by connecting the hydrogen production modules with the first connection part, and the hydrogen production module can be connected with the hydrogen by connecting the hydrogen production modules with the second connection part. A manufacturing apparatus can be made into the 2nd form.
In the hydrogen production apparatus of the present invention, it is preferable that the first and second connecting portions are separable from each hydrogen production module.
According to such a structure, the 1st connection part and the 2nd connection part can be replaced with the 1st form and the 2nd form, and the connection part suitable for the form can be used.

In the hydrogen production apparatus of the present invention, it is preferable that the connecting portion includes a magnet.
According to such a structure, each hydrogen production module can be connected by the attractive force of a magnet. This also makes it possible to easily separate the hydrogen production modules.
In the hydrogen production apparatus of the present invention, the connecting portion includes a water supply pipe that supplies an electrolytic solution to each hydrogen production module, a first gas exhaust pipe that discharges the first gas from each hydrogen production module, or a first gas discharge pipe that is connected to each hydrogen production module. It is preferable that it is the 2nd gas exhaust pipe which discharges 2 gas.
According to such a structure, a connection part can be used as a water supply pipe, a 1st gas exhaust pipe, or a 2nd gas exhaust pipe, and can reduce the number of parts.

In the hydrogen production apparatus of the present invention, each hydrogen production module includes a water supply port for supplying the electrolyte into the hydrogen production module, a first gas exhaust port for discharging the first gas, and a second gas for discharging the second gas. It is preferable to provide a liquid leakage prevention mechanism in the water supply port, the first gas discharge port, or the second gas discharge port.
According to such a configuration, when the water supply pipe, the first gas discharge pipe, or the second gas discharge pipe is removed from the hydrogen production module, it is possible to prevent the electrolyte from flowing out.
In the hydrogen production apparatus of the present invention, the hydrogen production module has a flexible and rollable sheet shape, the first form is an expanded form of the sheet-like hydrogen production module, and the second form is The sheet-like hydrogen production module is preferably rolled up.
According to such a configuration, by setting the hydrogen production apparatus to the first form, it is possible to increase the amount of light incident on the photoelectric conversion unit of the hydrogen production module, and by making the hydrogen production apparatus the second form, The installation area of the hydrogen production apparatus can be reduced. Moreover, the installation place of a hydrogen production apparatus can be changed easily.

The hydrogen production apparatus of the present invention further includes a switching unit that can be electrically connected to the first external circuit, and the switching unit outputs the electromotive force generated when the photoelectric conversion unit receives light to the first external circuit. It is preferable that the circuit that outputs the electromotive force generated when the photoelectric conversion unit receives light to the first and second electrolysis electrodes can be switched.
According to such a configuration, the electromotive force of the photoelectric conversion unit can be output to the first external circuit or the first or second electrolysis electrode as necessary, and the electromotive force of the photoelectric conversion unit is effectively utilized. can do.
In the hydrogen production apparatus of the present invention, the switching unit can be electrically connected to the second external circuit, and an electromotive force input from the second external circuit is used as the first electrolysis electrode and the second electrolysis electrode. It is preferable that the circuit can be switched to a circuit that outputs to the electrode and generates the first gas and the second gas from the electrolyte.
According to such a configuration, the first and second electrolysis electrodes can be effectively utilized. Further, when the hydrogen production apparatus is in the second form, the hydrogen production apparatus can be used as a compact water electrolysis apparatus.

In the hydrogen production apparatus of the present invention, when the photoelectric conversion unit receives light, an electromotive force is generated between the light receiving surface and the back surface, and the first electrolysis electrode is electrically connected to the back surface of the photoelectric conversion unit. It is preferable that the second electrolysis electrode is provided so that it can be electrically connected to the light receiving surface of the photoelectric conversion unit.
According to such a configuration, an electromotive force generated when the photoelectric conversion unit receives light can be output to the first electrolysis electrode and the second electrolysis electrode.
In the hydrogen production apparatus of the present invention, it is preferable that the hydrogen production module includes an insulating part between the second electrolysis electrode and the back surface of the photoelectric conversion part.
According to such a structure, the 2nd electrode for electrolysis and the back surface of a photoelectric conversion part can be electrically isolate | separated.

In the hydrogen production apparatus of the present invention, it is preferable that the hydrogen production module includes a first electrode that contacts a light receiving surface of the photoelectric conversion unit.
According to such a configuration, an electromotive force generated by the photoelectric conversion unit receiving light can be efficiently output.
In the hydrogen production apparatus of the present invention, it is preferable that the hydrogen production module includes a first conductive portion that electrically connects the first electrode and the second electrode for electrolysis.
According to such a structure, the light-receiving surface of a photoelectric conversion part and the 2nd electrode for electrolysis can be electrically connected.

In the hydrogen production apparatus of the present invention, the first conductive part is preferably provided in a contact hole that penetrates the photoelectric conversion part.
According to such a structure, the wiring distance between the light-receiving surface of a photoelectric conversion part and the 2nd electrode for electrolysis can be shortened.
In the hydrogen production apparatus of the present invention, the insulating portion is provided so as to cover a side surface of the photoelectric conversion portion, and the first conductive portion is a part of the insulating portion and covers a side surface of the photoelectric conversion portion. Preferably provided above.
According to such a configuration, the light receiving surface of the photoelectric conversion unit and the first conductive unit can be easily electrically connected.

In the hydrogen production apparatus of the present invention, the insulating portion is provided so as to cover a side surface of the photoelectric conversion portion, and the second electrolysis electrode is a part of the insulating portion and covers the side surface of the photoelectric conversion portion. It is preferable that the first electrode is provided on the first electrode and is in contact with the first electrode.
According to such a configuration, the light receiving surface of the photoelectric conversion unit and the first conductive unit can be easily electrically connected.
In the hydrogen production apparatus of the present invention, the photoelectric conversion unit preferably has a photoelectric conversion layer composed of a p-type semiconductor layer, an i-type semiconductor layer, and an n-type semiconductor layer.
According to such a configuration, an electromotive force can be generated when the photoelectric conversion unit receives light.

In the hydrogen production apparatus of the present invention, the photoelectric conversion unit receives light to generate a potential difference between the first and second regions on the back surface of the photoelectric conversion unit, and the first region is electrically connected to the first electrolysis electrode. It is preferable that the second area is provided so as to be electrically connected to the second electrolysis electrode.
According to such a configuration, an electromotive force generated when the photoelectric conversion unit receives light can be easily output to the first electrolysis electrode and the second electrolysis electrode.
In the hydrogen production apparatus of the present invention, the hydrogen production module includes an insulating portion between the first and second electrolysis electrodes and the back surface of the photoelectric conversion portion, and the insulating portion is located on the first section and the second area. It is preferred to have an opening on the area.
According to such a structure, the electron and the hole which arise when a photoelectric conversion part receives light can be isolate | separated efficiently.

In the hydrogen production apparatus of the present invention, the photoelectric conversion part is made of at least one semiconductor material having an n-type semiconductor part and a p-type semiconductor part, and one of the first and second areas is the n-type semiconductor part. It is preferable that the other part is a part of the p-type semiconductor part.
According to such a structure, the electron and the hole which arise when a photoelectric conversion part receives light can be isolate | separated efficiently.
In the hydrogen production apparatus of the present invention, it is preferable that the hydrogen production module includes a translucent substrate, and the photoelectric conversion unit is provided on the translucent substrate.
According to such a structure, a photoelectric conversion part can be formed easily.

In the hydrogen production apparatus of the present invention, the photoelectric conversion unit includes a plurality of photoelectric conversion layers connected in series, and the plurality of photoelectric conversion layers generate an electromotive force generated by receiving light in the first electrolysis electrode and the second electrolysis. It is preferable that it is provided so as to be supplied to the electrode.
According to such a configuration, the voltage of the electromotive force generated when the photoelectric conversion unit receives light can be increased.
In the hydrogen production apparatus of the present invention, one of the first electrolysis electrode and the second electrolysis electrode is a hydrogen generation unit that generates H ₂ from the electrolytic solution, and the other is oxygen generation that generates O ₂ from the electrolytic solution. The hydrogen generation part and the oxygen generation part are respectively a hydrogen generation catalyst that is a catalyst for the reaction that generates H ₂ from the electrolytic solution and an oxygen generation catalyst that is a catalyst for the reaction that generates O ₂ from the electrolytic solution. It is preferable to include.
According to such a configuration, hydrogen and oxygen can be efficiently produced from the electrolytic solution.

In the hydrogen production apparatus of the present invention, it is preferable that at least one of the hydrogen generation unit and the oxygen generation unit has a catalyst surface area larger than an area of a light receiving surface of the photoelectric conversion unit.
According to such a configuration, hydrogen and oxygen can be efficiently produced from the electrolytic solution.
In the hydrogen production apparatus of the present invention, it is preferable that at least one of the hydrogen generation unit and the oxygen generation unit is a porous conductor carrying a catalyst.
According to such a configuration, the surface area of the catalyst can be increased.

In the hydrogen production apparatus of the present invention, the hydrogen generation catalyst preferably includes at least one of Pt, Ir, Ru, Pd, Rh, Au, Fe, Ni, and Se.
According to such a configuration, hydrogen can be produced efficiently.
In the hydrogen production apparatus of the present invention, it is preferable that the oxygen generation catalyst contains at least one of Mn, Ca, Zn, Co, and Ir.
According to such a configuration, oxygen can be produced efficiently.

In the hydrogen production apparatus of the present invention, the hydrogen production module includes a translucent substrate, an electrolyte chamber, and a back substrate provided on the first electrolysis electrode and the second electrolysis electrode, It is preferable that the conversion unit is provided on the translucent substrate, and the electrolytic solution chamber is provided between the first electrolysis electrode and the second electrolysis electrode and the back substrate.
According to such a configuration, the electrolytic solution can be introduced into the electrolytic solution chamber, and the electrolytic solution can be brought into contact with the first and second electrolysis electrodes.
In the hydrogen production apparatus of the present invention, the hydrogen production module partitions an electrolyte chamber between the first electrolysis electrode and the back substrate and an electrolyte chamber between the second electrolysis electrode and the back substrate. It is preferable to provide a partition.
According to such a configuration, the first gas and the second gas can be separated by the partition wall.

In the hydrogen production apparatus of the present invention, the partition preferably includes an ion exchanger.
According to such a configuration, it is possible to eliminate the uneven proton concentration in the electrolyte chamber.
Moreover, this invention installs the hydrogen production apparatus of this invention with the 1st form so that the light-receiving surface of the said photoelectric conversion part may incline with respect to a horizontal surface, and electrolyte solution is supplied to the said hydrogen production module from the lower part of the said hydrogen production module. The first gas and the second electrolysis electrode are generated from the first electrolysis electrode and the second electrolysis electrode by introducing solar light into the light receiving surface of the photoelectric conversion unit, respectively. A method for producing hydrogen that exhausts one gas and a second gas is also provided.
According to the hydrogen production method of the present invention, hydrogen can be produced by making sunlight enter the photoelectric conversion unit.
Hereinafter, embodiments of the present invention will be described with reference to the drawings. The configurations shown in the drawings and the following description are merely examples, and the scope of the present invention is not limited to those shown in the drawings and the following description.

Diagram 1 of the hydrogen production device is a schematic plan view of a first embodiment of a hydrogen production device according to an embodiment of the present invention, FIG. 2 (a), second embodiment of a hydrogen production device according to an embodiment of the present invention (B) is the schematic side view. FIG. 3 is a schematic plan view of a hydrogen production module included in the hydrogen production apparatus of one embodiment of the present invention, and FIG. 4 is a schematic cross-sectional view of the hydrogen production module taken along a dotted line AA in FIG. 5 and 12 are schematic back views of a hydrogen production module included in the hydrogen production apparatus according to the embodiment of the present invention.
FIG. 6 is a schematic plan view of the first embodiment of the hydrogen production apparatus according to the embodiment of the present invention, and FIG. 7 is a schematic top view of the hydrogen production apparatus shown in FIG. FIG. 8 is a schematic plan view of the first embodiment of the hydrogen production apparatus according to one embodiment of the present invention. FIG. 9A is a schematic view of the second embodiment of the hydrogen production apparatus according to one embodiment of the present invention. It is a top view and FIG.9 (b) is the schematic side view. FIG. 10 is a schematic plan view of the first embodiment of the hydrogen production apparatus according to one embodiment of the present invention. FIG. 11A is a schematic diagram of the second embodiment of the hydrogen production apparatus according to one embodiment of the present invention. FIG. 11B is a side view, and FIG. 11B is a schematic top view thereof.

The hydrogen production apparatus 21 of the present embodiment is a hydrogen production apparatus 21 that can be deformed from the first form to the second form, or from the second form to the first form, and at least one hydrogen production provided in a deformable manner. The hydrogen production module 6 includes a photoelectric conversion unit 2 having a light receiving surface and a back surface, and a first electrolysis electrode 8 and a second electrolysis electrode 7 provided on the back surface side of the photoelectric conversion unit 2. The first and second electrolysis electrodes 8 and 7 are arranged such that when the light enters the light receiving surface of the photoelectric conversion unit 2 and the first and second electrolysis electrodes 8 and 7 come into contact with the electrolytic solution, the photoelectric conversion unit 2 The electrolysis solution generated by receiving light is used to electrolyze the electrolyte to generate the first gas and the second gas, respectively, and one of the first gas and the second gas is hydrogen. The other is oxygen, the first form is water The substantially entire light receiving surface included in the manufacturing apparatus 21 has a form capable of directly receiving sunlight, and the second form is on the light receiving surface side or the back surface side of the photoelectric conversion unit 2 included in one hydrogen production module 6. The photoelectric conversion unit 2 included in the same or different hydrogen production module 6 is located.
Hereinafter, the hydrogen production apparatus of this embodiment will be described.

1. Form of Hydrogen Production Apparatus The hydrogen production apparatus 21 of the present embodiment can be modified from the first form to the second form, or from the second form to the first form.
A 1st form is a form which the hydrogen production apparatus 21 can take, and the whole light-receiving surface of the photoelectric conversion part 2 contained in the hydrogen production apparatus 21 is a form which can receive sunlight directly. The first form may be a form in which 60, 70, 80, 90, 95 or 99% or more of the light receiving surface of the photoelectric conversion unit 2 included in the hydrogen production apparatus 21 can directly receive sunlight, This directly receivable range may be between two of the above numerical values.
The first form may be a form in which the hydrogen production module 6 is spread laterally or may be a form in which the hydrogen production module 6 is spread vertically, as compared with the second form, and is spread obliquely or randomly. Form may be sufficient.
The second form is a form that the hydrogen production apparatus 21 can take, and is included in the same or different hydrogen production module 6 on the light receiving surface side or the back surface side of the photoelectric conversion unit 2 contained in one hydrogen production module 6. In this configuration, the photoelectric conversion unit is located.
In the second embodiment, a part of the light receiving surface of the photoelectric conversion unit 2 included in one hydrogen production module 6 and a part of the light receiving surface of the photoelectric conversion unit 2 included in the same or different hydrogen production module 6 are provided. The form which overlaps may be sufficient. In the second embodiment, 50, 60, 70, 80, 90, or 99% or more of the light receiving surface of the photoelectric conversion unit 2 included in the hydrogen production module 6 is the same or different in the photoelectric conversion unit 2 included in the hydrogen production module 6. The light-receiving surface may be overlapped, and the overlapping range may be between two numerical values among the above numerical values. Further, among the light receiving surfaces of the photoelectric conversion unit 2 included in the hydrogen production apparatus 21, 50, 60, 70, 80, 90, or 99% or more of the light reception surface of the photoelectric conversion unit 2 included in the same or different hydrogen production module 6 The form which overlapped may be sufficient and this overlapping range may be between two numerical values among the said numerical values.
Further, the hydrogen production apparatus 21 may be provided so that it can be automatically deformed between the first form and the second form by a power unit such as a motor, and manually between the first form and the second form. It may be provided so that it can be modified. Further, when the hydrogen production apparatus 21 is provided so as to be automatically deformable, it may be controlled by the control unit so as to be automatically deformed according to the time zone, weather, season, or the like.
The hydrogen production apparatus 21 of this embodiment may consist of one hydrogen production module 6 or a plurality of hydrogen production modules 6. For example, it may consist of a plurality of hydrogen production modules 6 as shown in FIGS. 1, 2 and 6-9, or may consist of one hydrogen production module 6 as shown in FIGS. The at least one hydrogen production module provided in a deformable manner may be one in which one hydrogen production module 6 is deformed, and a plurality of hydrogen production modules 6 change their positional relationship. It may be something that deforms.

First, the case where the hydrogen production apparatus 21 of this embodiment is composed of a plurality of hydrogen production modules 6 will be described. In this case, the hydrogen production modules 6 can be connected by the connecting portion 12. The connecting portion 12 is a member that enables the hydrogen production apparatus 21 of the present embodiment to take both the first form and the second form.
The connecting portion 12 may have a structure including a rotating shaft such as the hinge member 26 shown in FIGS. 1 and 2, for example, the guide groove 55 and the rail portion 54 shown in FIGS. The at least one hydrogen production module 6 may have a structure that slides along the guide groove. For example, the hydrogen production module 6 has a magnet such as the magnet portion 57 shown in FIGS. May be. Moreover, the connection part 12 is piping which connects each hydrogen production module like the 1st gas exhaust pipe 22, the 2nd gas exhaust pipe 23, or the water supply pipe 24 shown, for example in FIG. It may be.

  When the connecting portion 12 has a structure having a rotating shaft like the hinge member 26 shown in FIGS. 1 and 2, the hinge member 26 (connecting portion 12) is provided between two adjacent hydrogen production modules 6, and a plurality of hydrogen The production modules 6 can be connected in a row. When connected in this manner, the two adjacent hydrogen production modules 6 can be opened and closed with the hinge member 26 as a rotation axis. Further, by providing the hinge members 26 so that the bending directions of the hinge members 26 are alternately changed, the hydrogen production apparatus 21 can be folded into a bellows fold. For example, as shown in FIG. 1, by transforming the hinge member 26 so that each of the hydrogen production modules 6 a to 6 d connected by the hinge member 26 spreads, the hydrogen production device 21 is converted into the photoelectric conversion unit 2 included in the hydrogen production device 21. It is possible to adopt a first configuration in which substantially the entire light receiving surface of the first light can directly receive sunlight. Thereby, the amount of light incident on the light receiving surface of the photoelectric conversion unit 2 of the hydrogen production modules 6a to 6d can be increased, and the amount of hydrogen generation can be increased.

  Further, the first embodiment of the hydrogen production apparatus 21 as shown in FIG. 1 is modified so that the light receiving surface of the photoelectric conversion unit 2 included in the first hydrogen production module 6a as shown in FIG. It can be set as the form with which the light-receiving surface of the photoelectric conversion part 2 contained in the module 6b overlapped. In addition, by this, the hydrogen production apparatus 21 is configured such that the photoelectric conversion unit 2 included in the hydrogen production modules 6b, 6c, and 6d is positioned on the back side of the photoelectric conversion unit 2 included in the hydrogen production module 6a. can do. Specifically, the hydrogen production modules 6a to 6d connected by the hinge portion 26 shown in FIG. 1 can be folded into a bellows fold so as to be transformed into the second form as shown in FIG. As a result, the hydrogen production apparatus 21 can be made compact, and the installation area of the hydrogen production apparatus 21 can be reduced. In addition, the 1st gas exhaust pipe 22, the 2nd gas exhaust pipe 23, or the water supply pipe 24 which connected each hydrogen production module 6 in the 1st form shown in FIG. Can be provided. By this, the 1st gas exhaust pipe 22, the 2nd gas exhaust pipe 23, or the water supply pipe 24 is isolate | separated from each hydrogen production module 6, and the hydrogen production apparatus 21 can be changed from a 1st form to a 2nd form. it can. In this case, a liquid leakage prevention mechanism 25 can be provided in the first gas discharge port 20, the second gas discharge port 19, the water supply port 18, or the water supply pipe 24 of the hydrogen production module 6. Thus, even when the first gas discharge pipe 22, the second gas discharge pipe 23, or the water supply pipe 24 is separated from the hydrogen production module 6, it is possible to prevent the electrolyte from leaking. The liquid leakage prevention mechanism 25 may be composed of, for example, a backflow prevention valve including a spring and a valve body, or may be composed of a marble check valve.

Moreover, the 1st gas exhaust pipe 22, the 2nd gas exhaust pipe 23, or the water supply pipe 24 may consist of a member of a different form by the case where the hydrogen production apparatus 21 is a 1st form, and the case of a 2nd form. Thereby, for example, the first gas exhaust pipe 22, the second gas exhaust pipe 23, or the water supply pipe 24 shown in FIG. 1, the first gas exhaust pipe 22, the second gas exhaust pipe 23 shown in FIG. Or like the water supply pipe | tube 24, the member from which the width | variety of the part connected with each hydrogen production module 6 differs by a 1st form and a 2nd form can be used. Thereby, in the second embodiment, the piping distance for recovering hydrogen can be shortened, and when hydrogen is generated by electrolyzing the electrolyte using external power in the hydrogen production device 21 of the second embodiment, Hydrogen can be recovered efficiently.
Moreover, the 1st gas exhaust pipe 22, the 2nd gas exhaust pipe 23, or the water supply pipe 24 may consist of a pipe | tube which has a stretching property or a softness | flexibility. Since these tubes have elasticity or flexibility, the hydrogen production apparatus 21 is transformed from the first configuration to the second configuration or from the second configuration to the first configuration without removing these tubes from the hydrogen production module 6. be able to. Moreover, when these pipe | tubes have elasticity, when the hydrogen production apparatus 21 is made into a 2nd form, piping distance can be shortened. As the tube having elasticity and flexibility, for example, a bellows tube can be used, and as the tube having flexibility, for example, a rubber tube can be used.
In addition, the description about the 1st gas exhaust pipe 22, the 2nd gas exhaust pipe 23, or the water supply pipe 24 mentioned above is applicable also about the other example mentioned later unless a contradiction arises.

  When the connecting portion 12 has the guide groove 55 and the at least one hydrogen production module 6 slides along the guide groove 55, more specifically, as shown in FIGS. When the guide groove 55 is provided on the back surface side and the rail portion 54 is provided on the light receiving surface side of the hydrogen production apparatus 21, the hydrogen production modules 6 b, c, and d are connected so as to slide along the guide groove 55. The part 12 can be provided, and the hydrogen production modules can be connected in a row by the connecting part 12. When the hydrogen production modules are connected in this way, the hydrogen production modules 21 b, c, d slide along the guide groove 55 provided on the back surface of the adjacent hydrogen production module 6, whereby the hydrogen production apparatus 21 is The first form can be changed to the second form, and the second form can be changed to the first form.

  For example, as shown in FIGS. 6 and 7, the hydrogen production apparatus 21 is fitted with the end of the guide groove 55 provided in the hydrogen production module 6a and the end of the rail portion 54 provided in the hydrogen production module 6b. The end of the guide groove 55 of the hydrogen production module 6b and the end of the rail portion 54 of the hydrogen production module 6c are fitted, and the end of the guide groove 55 of the hydrogen production module 6c and the end of the rail portion 54 of the hydrogen production module 6d are fitted. By adopting a configuration in which the hydrogen production device 21 is fitted, the hydrogen production device 21 can be in a first configuration in which substantially the entire light receiving surface of the photoelectric conversion unit 2 included in the hydrogen production device 21 can directly receive sunlight. . Thereby, the amount of light incident on the light receiving surface of the photoelectric conversion unit 2 of the hydrogen production modules 6a to 6d can be increased, and the amount of hydrogen generation can be increased.

  The hydrogen production modules 6b, c, d included in the hydrogen production apparatus 21 of the first embodiment as shown in FIGS. 6 and 7 are slid along the guide groove provided on the back surface of the adjacent hydrogen production module. Thus, the hydrogen production modules 6a to 6d can be stacked, and the hydrogen production apparatus 21 is connected to the photoelectric conversion unit 2 included in the hydrogen production module 6a on the back side of the photoelectric production unit 6b, 6c, 6d. It can be set as the 2nd form in which the conversion part 2 is located. Moreover, the hydrogen production apparatus 21 can be deformed so that the light receiving surface of the photoelectric conversion unit 2 of the hydrogen production module 6b and the light reception surface of the photoelectric conversion unit 2 of the hydrogen production module 6a overlap. As a result, the hydrogen production apparatus 21 can be made compact, and the installation area of the hydrogen production apparatus 21 can be reduced.

  In the example shown in FIGS. 6 and 7, the guide groove is provided on the back surface of the hydrogen production module 6, but the guide groove may be provided on the light receiving surface of the hydrogen production module 6, or may be provided on the upper part, It may be provided in the lower part. In addition, the guide groove may be provided in the connecting part 6 which is a separate member from the hydrogen production module 6, and may be in the form of a groove for standing a door or a shoji, for example.

The connection part 12 may be such that each hydrogen production module can be separated. As such a connection part 12, for example, each hydrogen production device module may be connected by magnetic force of a magnet, or each hydrogen production module may be connected by a built-in structure, Each hydrogen production module may be connected by a combination of a structure and a female screw structure. When the first gas exhaust pipe 22, the second gas exhaust pipe 19 or the water supply pipe 24 is separable from the hydrogen production module 6, the connecting portion 12 is connected to the first gas exhaust pipe 22, the second gas exhaust pipe 19 or the water supply. It may be a tube 24.
In this case, the hydrogen production modules 6 may be connected by different connecting portions 12 depending on whether the hydrogen production apparatus 21 takes the first form or the second form.
Hereinafter, an example in which each hydrogen production module 6 is connected by a connecting portion including a magnet will be described. However, when the connecting portion 12 has a fitting structure, a screw structure, a pipe structure, etc. This is the case as long as there is no contradiction in the explanation of replacing part 12.

As shown in FIG. 8, when the connecting portion 12 is composed of the magnet portion 57 and each hydrogen production module 6 has the magnet portion 57 (first connecting portion 12) on its side surface, the magnet portion is provided between the side surfaces of each hydrogen production module 6. 57 can be connected. Thereby, the hydrogen production apparatus 21 can be in a first form in which substantially the entire light receiving surface of the photoelectric conversion unit 2 included in the hydrogen production apparatus 21 can directly receive sunlight. Thereby, the amount of light incident on the light receiving surface of the photoelectric conversion unit 2 of the hydrogen production modules 6a to 6d can be increased, and the amount of hydrogen generation can be increased.
The hydrogen production apparatus 21 as shown in FIG. 8 includes, for example, each hydrogen production module in which the first gas discharge pipe 22, the second gas discharge pipe 19, and the water supply pipe 24 are removed from each hydrogen production module 6 and connected by each magnet unit 57. By separating 6, each hydrogen production module 6 can be separated.

As shown in FIG. 9, when the connecting portion 12 includes the magnet portion 57 and each hydrogen production module 6 has the magnet portion 57 (second connecting portion 12) on the light receiving surface side and the back surface side, two adjacent hydrogen producing units are produced. The light receiving surface and the back surface of the module 6 can be connected. Thus, the hydrogen production apparatus 21 is set to the second configuration in which the photoelectric conversion unit 2 included in the hydrogen production modules 6b, 6c, and 6d is located on the back side of the photoelectric conversion unit 2 included in the hydrogen production module 6a. Can do. Moreover, the hydrogen production apparatus 21 can be configured such that the light receiving surface of the photoelectric conversion unit 2 included in the hydrogen production module 6b and the light reception surface of the photoelectric conversion unit 2 included in the hydrogen production module 6a overlap.
As a result, the hydrogen production apparatus 21 can be made compact, and the installation area of the hydrogen production apparatus 21 can be reduced.
In addition, the example in the case where the hydrogen production apparatus 21 mentioned above consists of the several hydrogen production module 6 can also be combined, respectively. Moreover, the 2nd form may be the form which combined the some hydrogen production apparatus 21 with the connection part. Thereby, the installation place of the hydrogen production apparatus 21 can be used more effectively.

Next, the case where the hydrogen production apparatus 21 of this embodiment consists of one hydrogen production module 6 will be described. In this case, for example, the hydrogen production module 6 can be formed into a flexible sheet. Such a hydrogen production module 6 can be produced, for example, by forming the photoelectric conversion unit 2 and the first and second electrolysis electrodes on a flexible sheet.
When the hydrogen production module 6 included in the hydrogen production apparatus 21 has a flexible sheet shape, the hydrogen production module 6 is deformed, so that the hydrogen production apparatus 21 changes from the first form to the second form or the second form. The form can be changed to the first form. The flexible sheet-like hydrogen production module 6 may be rollable.
For example, by forming a flexible sheet-like hydrogen production module 6 that can be rolled up, the hydrogen production apparatus 21 is configured so that the entire light receiving surface of the photoelectric conversion unit 2 included in the hydrogen production apparatus 21 is substantially the same. It can be set as the 1st form which can receive sunlight directly.
For example, by expanding the hydrogen production module 6 as shown in FIG. 10, the hydrogen production apparatus 21 can be in the first form. As a result, the amount of light incident on the light receiving surface of the photoelectric conversion unit 2 of the hydrogen production module 6 can be increased, and the amount of hydrogen generated can be increased.

Further, for example, by forming a sheet-like hydrogen production module 6 that is flexible and can be rolled up, the hydrogen production apparatus 21 can receive a part of the photoelectric conversion unit 2 included in the hydrogen production module 6. It can be set as the 2nd form by which the other one part photoelectric conversion part 2 contained in the same hydrogen production module 6 is located in the surface side or a back surface side. In addition, as a result, the hydrogen production apparatus 21 can be used for a part of the light receiving surface of the photoelectric conversion unit 2 included in the hydrogen production module 6 and the other light receiving surface of the photoelectric conversion unit 2 included in the same hydrogen production module 6. It can be set as the form which a part overlaps.
For example, when the hydrogen production module 6 is rolled up as shown in FIG. 11, the hydrogen production apparatus 21 can be in the second form. As a result, the hydrogen production apparatus 21 can be made compact, and the installation area of the hydrogen production apparatus 21 can be reduced. In addition, the form of the hydrogen production apparatus in the second form is not limited to the form in which the hydrogen production module 6 is wound up. For example, the form in which the hydrogen production module 6 is folded in a bellows may be used. It may be a folded form.
In addition, the case where this hydrogen production apparatus 21 consists of one hydrogen production module 6 can also be combined with the example where the above-mentioned hydrogen production apparatus 21 consists of a plurality of hydrogen production modules 6. Moreover, the 2nd form may be the form which combined the some hydrogen production apparatus 21 with the connection part. Thereby, the installation place of the hydrogen production apparatus 21 can be used more effectively.

2. Hydrogen production module The hydrogen production module 6 includes a photoelectric conversion unit 2 having a light receiving surface and a back surface thereof, a first electrolysis electrode 8 and a second electrolysis electrode 7 provided on the back surface side of the photoelectric conversion unit 2, When light is incident on the light receiving surface of the photoelectric conversion unit 2 and the first and second electrolysis electrodes 8 and 7 are in contact with the electrolytic solution, the first and second electrolysis electrodes 8 and 7 are received by the photoelectric conversion unit 2. The electrolytic solution is electrolyzed using the electromotive force generated by the generation, and the first gas and the second gas can be generated, respectively.
The hydrogen production apparatus 21 may include one hydrogen production module 6 or a plurality of hydrogen production modules 6.
13 to 20 are schematic cross-sectional views of the hydrogen production module 6 included in the hydrogen production apparatus according to the embodiment of the present invention, and correspond to the schematic cross-sectional view of the hydrogen production module taken along the dotted line AA in FIG.

3. Translucent substrate The translucent substrate 1 may be provided in the hydrogen production module 6 of the present embodiment. Moreover, the photoelectric conversion part 2 may be provided on the translucent board | substrate 1 so that a light-receiving surface may become the translucent board | substrate 1 side. In addition, when the photoelectric conversion part 2 consists of semiconductor substrates etc. and has fixed intensity | strength, the translucent board | substrate 1 can be abbreviate | omitted. Moreover, when the photoelectric conversion part 2 can be formed on a flexible material such as a resin film, the translucent substrate 1 can be omitted. When the photoelectric conversion unit 2 is formed on a flexible material, the hydrogen production module 6 can be formed into a flexible sheet, and the hydrogen production module 21 is deformed to deform the hydrogen production module 21. Can be changed from the first form to the second form or from the second form to the first form.

In addition, since the sunlight is received by the light receiving surface of the photoelectric conversion unit 2, the translucent substrate 1 is preferably transparent and has high light transmittance. However, it is possible to efficiently enter light into the photoelectric conversion unit 2. If it is a simple structure, there is no restriction | limiting in the light transmittance.
As a substrate material having a high light transmittance, for example, a transparent rigid material such as soda glass, quartz glass, Pyrex (registered trademark), or a synthetic quartz plate, or a transparent resin plate or film material is preferably used. In view of chemical and physical stability, it is preferable to use a glass substrate.
On the surface of the translucent substrate 1 on the photoelectric conversion unit 2 side, a fine uneven structure can be formed so that incident light is effectively irregularly reflected on the surface of the photoelectric conversion unit 2. This fine concavo-convex structure can be formed by a known method such as reactive ion etching (RIE) treatment or blast treatment.

4). 1st electrode The 1st electrode 4 can be provided on the translucent board | substrate 1, and can be provided so that the light-receiving surface of the photoelectric conversion part 2 may be contacted. Moreover, the 1st electrode 4 may have translucency. Moreover, the 1st electrode 4 may be directly provided in the light-receiving surface of the photoelectric conversion part 2, when the translucent board | substrate 1 can be abbreviate | omitted. The first electrode 4 can be electrically connected to the second electrolysis electrode 7. By providing the first electrode 4, the current flowing between the light receiving surface of the photoelectric conversion unit 2 and the second electrolysis electrode 7 can be increased. Moreover, when the photoelectric conversion part 2 produces an electromotive force between the 1st area and the 2nd area of the back surface of the photoelectric conversion part 2 like FIG. 19, 20, the 1st electrode 4 is unnecessary.
The first electrode 4 may be electrically connected to the second electrolysis electrode 7 via the first conductive portion 9 as shown in FIGS. 4, 14 and 17, and the second electrolysis electrode 7 as shown in FIG. You may contact with. Moreover, the 1st electrode 4 can be electrically connected with the electrode 7 for 2nd electrolysis via the switching part 10 and the wiring 52 in the case like FIG.
The first electrode 4 may be made of a transparent conductive film such as ITO or SnO _2, or may be made of a metal finger electrode such as Ag or Au.

A case where the first electrode 4 is a transparent conductive film will be described below.
The transparent conductive film can be used to facilitate contact between the light receiving surface of the photoelectric conversion unit 2 and the second electrolysis electrode 7.
What is generally used as a transparent electrode can be used. Specifically, In—Zn—O (IZO), In—Sn—O (ITO), ZnO—Al, Zn—Sn—O, SnO _{2 and the} like can be given. The transparent conductive film preferably has a sunlight transmittance of 85% or more, particularly 90% or more, and particularly 92% or more. This is because the photoelectric conversion unit 2 can absorb light efficiently.
As a method for producing the transparent conductive film, a known method can be used, and examples thereof include sputtering, vacuum deposition, sol-gel method, cluster beam deposition method, and PLD (Pulse Laser Deposition) method.

5. Photoelectric Conversion Unit The photoelectric conversion unit 2 has a light receiving surface and a back surface thereof, and a first electrolysis electrode 8 and a second electrolysis electrode 7 are provided on the back surface side of the photoelectric conversion unit 2. The light receiving surface is a surface that receives light for photoelectric conversion, and the back surface is the back surface of the light receiving surface. The light receiving surface of the hydrogen production device 21 is the surface of the hydrogen production device 21 on the same side as the light reception surface of the photoelectric conversion unit 2, and the back surface of the hydrogen production device 21 is the same side as the back surface of the photoelectric conversion unit 2. It is the surface of the hydrogen production apparatus 21.
Moreover, the photoelectric conversion part 2 can be provided on the translucent substrate 1 provided with the first electrode 4 with the light receiving surface facing down. For example, an electromotive force may be generated between the light receiving surface and the back surface of the photoelectric conversion unit 2 as illustrated in FIGS. 4 and 13 to 18, and the back surface of the photoelectric conversion unit 2 as illustrated in FIGS. An electromotive force may be generated between the first area and the second area. 19 and 20 can be formed by a semiconductor substrate on which an n-type semiconductor region 37 and a p-type semiconductor region 36 are formed.
Although the shape of the photoelectric conversion part 2 is not specifically limited, For example, it can be set as a square shape.
The photoelectric conversion unit 2 is not particularly limited as long as it can separate charges by incident light and generates an electromotive force. For example, the photoelectric conversion unit using a silicon-based semiconductor or the photoelectric conversion unit using a compound semiconductor A photoelectric conversion part using a dye sensitizer, a photoelectric conversion part using an organic thin film, and the like.

  When either one of the first gas and the second gas is hydrogen and the other is oxygen, the photoelectric conversion unit 2 receives light in the first electrolysis electrode 8 and the second electrolysis electrode 7. It is necessary to use a material that generates an electromotive force necessary for generating hydrogen and oxygen. The potential difference between the first electrolysis electrode 8 and the second electrolysis electrode 7 needs to be larger than the theoretical voltage (1.23 V) for water decomposition, and for this purpose, a sufficiently large potential difference needs to be generated in the photoelectric conversion unit 2. There is. Therefore, it is preferable that the photoelectric conversion unit 2 connects two or more junctions in series such as a pn junction to generate an electromotive force. For example, the photoelectric conversion layers provided side by side as shown in FIGS. 17 and 20 can be connected in series by the third conductive portion 33.

  Examples of the material that performs photoelectric conversion include silicon-based semiconductors, compound semiconductors, and materials based on organic materials, and any photoelectric conversion material can be used. In order to increase the electromotive force, these photoelectric conversion materials can be stacked. In the case of stacking, it is possible to form a multi-junction structure with the same material, but stacking multiple photoelectric conversion layers with different optical band gaps and complementing the low sensitivity wavelength region of each photoelectric conversion layer mutually By doing so, incident light can be efficiently absorbed over a wide wavelength region. The plurality of photoelectric conversion layers preferably have different band gaps. According to such a configuration, the electromotive force generated in the photoelectric conversion unit 2 can be increased, and the electrolytic solution can be electrolyzed more efficiently.

Moreover, it is possible to interpose a conductor such as a transparent conductive film between the layers in order to improve the serial connection characteristics between the photoelectric conversion layers and match the photocurrent generated in the photoelectric conversion unit 2. Thereby, it becomes possible to suppress deterioration of the photoelectric conversion unit 2.
An example of the photoelectric conversion unit 2 will be specifically described below. The photoelectric conversion unit 2 may be a combination of these. Moreover, the example of the following photoelectric conversion parts 2 can also be used as a photoelectric conversion layer as long as there is no contradiction.

5-1. Photoelectric conversion part using a silicon-based semiconductor Examples of the photoelectric conversion part 2 using a silicon-based semiconductor include a single crystal type, a polycrystalline type, an amorphous type, a spherical silicon type, and combinations thereof. Any of them can have a pn junction in which a p-type semiconductor and an n-type semiconductor are joined. Further, a pin junction in which an i-type semiconductor is provided between a p-type semiconductor and an n-type semiconductor may be provided. Further, it may have a plurality of pn junctions, a plurality of pin junctions, or a pn junction and a pin junction.
The silicon-based semiconductor is a semiconductor containing silicon, such as silicon, silicon carbide, or silicon germanium. In addition, silicon or the like in which n-type impurities or p-type impurities are added is included, and crystalline, amorphous, or microcrystalline silicon is also included.
In addition, the photoelectric conversion unit 2 using a silicon-based semiconductor may be a thin film or a thick photoelectric conversion layer formed on the translucent substrate 1, or a pn junction or a wafer such as a silicon wafer. A pin junction may be formed, or a thin film photoelectric conversion layer may be formed on a wafer having a pn junction or a pin junction.

An example of forming the photoelectric conversion unit 2 using a silicon-based semiconductor is shown below.
A first conductivity type semiconductor layer is formed on the first electrode 4 laminated on the translucent substrate 1 by a method such as a plasma CVD method. As the first conductive type semiconductor layer, a p ⁺ type or n ⁺ type amorphous Si thin film doped with a conductivity type determining impurity atom concentration of about 1 × 10 ^{18 to} 5 × 10 ²¹ / cm ³ , or many A crystalline or microcrystalline Si thin film is used. The material of the first conductivity type semiconductor layer is not limited to Si, and it is also possible to use a compound such as SiC, SiGe, or Si _x O _1-x .

On the first conductivity type semiconductor layer thus formed, a polycrystalline or microcrystalline crystalline Si thin film is formed as a crystalline Si photoactive layer by a method such as plasma CVD. The conductivity type is the first conductivity type having a lower doping concentration than the first conductivity type semiconductor, or the i conductivity type. The material for the crystalline Si-based photoactive layer is not limited to Si, and it is also possible to use a compound such as SiC, SiGe, or Si _x O _1-x .

Next, in order to form a semiconductor junction on the crystalline Si-based photoactive layer, a second conductivity type semiconductor layer having a conductivity type opposite to the first conductivity type semiconductor layer is formed by a method such as plasma CVD. As the second conductive type semiconductor layer, an n ⁺ type or p ⁺ type amorphous Si thin film doped with about 1 × 10 ^{18 to} 5 × 10 ²¹ / cm ³ of a conductivity type determining impurity atom, or polycrystalline Alternatively, a microcrystalline Si thin film is used. The material of the second conductivity type semiconductor layer is not limited to Si, and it is also possible to use a compound such as SiC, SiGe, or Si _x O _1-x . In order to further improve the bonding characteristics, it is possible to insert a substantially i-type non-single-crystal Si-based thin film between the crystalline Si-based photoactive layer and the second conductive type semiconductor layer. In this manner, one photoelectric conversion layer closest to the light receiving surface can be stacked.

  Subsequently, a second photoelectric conversion layer is formed. The second photoelectric conversion layer is composed of a first conductivity type semiconductor layer, a crystalline Si-based photoactive layer, and a second conductivity type semiconductor layer, each layer corresponding to the first photoelectric conversion layer. The first conductive type semiconductor layer, the crystalline Si-based photoactive layer, and the second conductive type semiconductor layer are formed. When a potential sufficient for water splitting cannot be obtained with a two-layer tandem, it is preferable to take a three-layer structure or more. However, the volume crystallization fraction of the crystalline Si photoactive layer of the second photoelectric conversion layer is preferably higher than that of the first crystalline Si photoactive layer. Similarly, when three or more layers are laminated, it is preferable to increase the volume crystallization fraction as compared with the lower layer. This increases the absorption in the long wavelength region, shifts the spectral sensitivity to the long wavelength side, and can improve the sensitivity in a wide wavelength region even when the photoactive layer is configured using the same Si material. It is because it becomes. That is, by using a tandem structure with Si having different crystallization rates, the spectral sensitivity is widened, and light can be used with high efficiency. At this time, if the low crystallization rate material is not on the light receiving surface side, high efficiency cannot be achieved. Further, when the crystallization rate is lowered to 40% or less, the amorphous component increases and deterioration occurs.

Next, the example of formation of the photoelectric conversion part 2 using a silicon substrate is shown below.
As the silicon substrate, a single crystal silicon substrate, a polycrystalline silicon substrate, or the like can be used, and may be p-type, n-type, or i-type. An n-type semiconductor portion 37 is formed by doping an n-type impurity such as P into a part of the silicon substrate by thermal diffusion or ion implantation, and a p-type impurity such as B is heated on the other part of the silicon substrate. The p-type semiconductor portion 36 can be formed by doping by diffusion or ion implantation. Thus, pn junction in the silicon substrate, pin junction can be formed and npp ⁺ junction or pnn ⁺ junction, it is possible to form a photoelectric conversion unit 2.

Each of the n-type semiconductor portion 37 and the p-type semiconductor portion 36 can form one region on the silicon substrate as shown in FIGS. 19 and 20, and either of the n-type semiconductor region 37 and the p-type semiconductor region 36 can be formed. A plurality of these can be formed. Alternatively, as shown in FIG. 20, the photoelectric conversion unit 2 can be formed by arranging the silicon substrates on which the n-type semiconductor region 37 and the p-type semiconductor region 36 are arranged side by side and connecting them in series by the third conductive unit 33.
Note that, although described with reference to a silicon substrate, pn junction, pin junction, may use other semiconductor substrate or the like can be formed npp ⁺ junction or pnn ⁺ junction. In addition, as long as the n-type semiconductor portion 37 and the p-type semiconductor portion 36 can be formed, the semiconductor layer is not limited to the semiconductor substrate, and may be a semiconductor layer formed on the substrate.

5-2. Photoelectric conversion part using a compound semiconductor The photoelectric conversion part using a compound semiconductor is, for example, GaP, GaAs, InP, InAs, or II-VI group elements composed of III-V group elements, CdTe / CdS, Examples thereof include those in which a pn junction is formed using CIGS (Copper Indium Gallium DiSelenide) composed of a group I-III-VI.

An example of a method for manufacturing a photoelectric conversion unit using a compound semiconductor is shown below. In this manufacturing method, all film-forming processes are continuously performed using a metal organic chemical vapor deposition (MOCVD) apparatus. Done. As a group III element material, for example, an organic metal such as trimethylgallium, trimethylaluminum, or trimethylindium is supplied to the growth apparatus using hydrogen as a carrier gas. For example, a gas such as arsine (AsH ₃ ), phosphine (PH ₃ ), and stibine (SbH ₃ ) is used as the material of the group V element. As a dopant of p-type impurities or n-type impurities, for example, diethyl zinc for p-type conversion, monosilane (SiH ₄ ), disilane (Si ₂ H ₆ ), hydrogen selenide (H ₂ Se) for n-type conversion. Etc. are used. These source gases can be thermally decomposed by supplying them onto a substrate heated to, for example, 700 ° C., and a desired compound semiconductor material film can be epitaxially grown. The composition of these growth layers can be controlled by the gas composition to be introduced, and the film thickness can be controlled by the gas introduction time. When multi-junction laminating these photoelectric conversion parts, it is possible to form a growth layer with excellent crystallinity by adjusting the lattice constant between layers as much as possible, and to improve the photoelectric conversion efficiency. Become.

  In addition to the portion where the pn junction is formed, for example, a known window layer on the light receiving surface side or a known electric field layer on the non-light receiving surface side may be provided to improve carrier collection efficiency. Further, a buffer layer for preventing diffusion of impurities may be provided.

5-3. Photoelectric conversion part using a dye sensitizer The photoelectric conversion part using a dye sensitizer is mainly composed of, for example, a porous semiconductor, a dye sensitizer, an electrolyte, a solvent, and the like.
As a material constituting the porous semiconductor, for example, one or more kinds of known semiconductors such as titanium oxide, tungsten oxide, zinc oxide, barium titanate, strontium titanate, cadmium sulfide can be selected. As a method for forming a porous semiconductor on a substrate, a paste containing semiconductor particles is applied by a screen printing method, an ink jet method and the like, dried or baked, a method of forming a film by a CVD method using a raw material gas, etc. , PVD method, vapor deposition method, sputtering method, sol-gel method, method using electrochemical oxidation-reduction reaction, and the like.

  As the dye sensitizer adsorbed on the porous semiconductor, various dyes having absorption in the visible light region and the infrared light region can be used. Here, in order to firmly adsorb the dye to the porous semiconductor, the carboxylic acid group, carboxylic anhydride group, alkoxy group, sulfonic acid group, hydroxyl group, hydroxylalkyl group, ester group, mercapto group, phosphonyl in the dye molecule It is preferable that a group or the like is present. These functional groups provide an electrical bond that facilitates electron transfer between the excited state dye and the conduction band of the porous semiconductor.

  Examples of dyes containing these functional groups include ruthenium bipyridine dyes, quinone dyes, quinone imine dyes, azo dyes, quinacridone dyes, squarylium dyes, cyanine dyes, merocyanine dyes, and triphenylmethane dyes. Xanthene dyes, porphyrin dyes, phthalocyanine dyes, berylene dyes, indigo dyes, naphthalocyanine dyes, and the like.

  Examples of the method for adsorbing the dye to the porous semiconductor include a method in which the porous semiconductor is immersed in a solution in which the dye is dissolved (dye adsorption solution). The solvent used in the dye adsorption solution is not particularly limited as long as it dissolves the dye, and specifically, alcohols such as ethanol and methanol, ketones such as acetone, ethers such as diethyl ether and tetrahydrofuran. Nitrogen compounds such as acetonitrile, aliphatic hydrocarbons such as hexane, aromatic hydrocarbons such as benzene, esters such as ethyl acetate, water, and the like.

The electrolyte is composed of a redox pair and a solid medium such as a liquid or polymer gel holding the redox pair.
In general, iron- and cobalt-based metals and halogen substances such as chlorine, bromine, and iodine are preferably used as the redox pair, and metal iodides such as lithium iodide, sodium iodide, and potassium iodide and iodine. The combination of is preferably used. Furthermore, imidazole salts such as dimethylpropylimidazole iodide can also be mixed.

  As the solvent, carbonate compounds such as propylene carbonate, nitrile compounds such as acetonitrile, alcohols such as ethanol and methanol, water, aprotic polar substances, and the like are used. Of these, carbonate compounds and nitrile compounds are preferred. Used.

5-4. Photoelectric conversion part using organic thin film Photoelectric conversion part 2 using an organic thin film is an electron hole transport layer composed of an organic semiconductor material having electron donating properties and electron accepting properties, or an electron transport layer having electron accepting properties. And a hole transport layer having an electron donating property may be laminated.
The electron-donating organic semiconductor material is not particularly limited as long as it has a function as an electron donor, but it is preferable that a film can be formed by a coating method, and among them, an electron-donating conductive polymer is preferably used. The

  Here, the conductive polymer means a π-conjugated polymer, which is composed of a π-conjugated system in which double bonds or triple bonds containing carbon-carbon or hetero atoms are alternately linked to single bonds, and exhibits semiconducting properties. Point.

  Examples of the electron-donating conductive polymer material include polyphenylene, polyphenylene vinylene, polythiophene, polycarbazole, polyvinyl carbazole, polysilane, polyacetylene, polypyrrole, polyaniline, polyfluorene, polyvinyl pyrene, polyvinyl anthracene, and derivatives, Examples thereof include a polymer, a phthalocyanine-containing polymer, a carbazole-containing polymer, and an organometallic polymer. Among these, thiophene-fluorene copolymer, polyalkylthiophene, phenyleneethynylene-phenylene vinylene copolymer, fluorene-phenylene vinylene copolymer, thiophene-phenylene vinylene copolymer, and the like are preferably used.

The electron-accepting organic semiconductor material is not particularly limited as long as it has a function as an electron acceptor. However, it is preferable that a film can be formed by a coating method, and among them, an electron-donating conductive polymer is preferably used. The
Examples of the electron-accepting conductive polymer include polyphenylene vinylene, polyfluorene, and derivatives and copolymers thereof, or carbon nanotubes, fullerene and derivatives thereof, CN group or CF ₃ group-containing polymers, and -CF thereof. Examples thereof include _3- substituted polymers.

In addition, an electron-accepting organic semiconductor material doped with an electron-donating compound, an electron-donating organic semiconductor material doped with an electron-accepting compound, or the like can be used. Examples of the electron-accepting conductive polymer material doped with the electron-donating compound include the above-described electron-accepting conductive polymer material. As the electron-donating compound to be doped, for example, a Lewis base such as an alkali metal such as Li, K, Ca, or Cs or an alkaline earth metal can be used. The Lewis base acts as an electron donor. Examples of the electron-donating conductive polymer material doped with the electron-accepting compound include the above-described electron-donating conductive polymer material. As the electron-accepting compound to be doped, for example, a Lewis acid such as FeCl ₃ , AlCl ₃ , AlBr ₃ , AsF ₆ or a halogen compound can be used. In addition, Lewis acid acts as an electron acceptor.

  In the photoelectric conversion unit 2 shown above, it is assumed that sunlight is received and photoelectric conversion is primarily performed. However, it is emitted from a fluorescent lamp, an incandescent lamp, an LED, or a specific heat source depending on the application. It is also possible to perform photoelectric conversion by irradiating artificial light such as light.

6). Second Electrode The second electrode 5 can be provided on the back surface of the photoelectric conversion unit 2. The second electrode 5 can also be provided between the back surface of the photoelectric conversion unit 2 and the first electrolysis electrode 8 and between the back surface of the photoelectric conversion unit 2 and the insulating unit 11. The second electrode 5 can be electrically connected to the first electrolysis electrode 8. By providing the second electrode 5, it is possible to reduce ohmic cross between the back surface of the photoelectric conversion unit 2 and the first electrolysis electrode 8. The second electrode 5 may be in contact with the first electrolysis electrode 8. Further, the second electrode 5 may be electrically connected to the first electrolysis electrode 8 via the switching unit 10 and the wiring 52.
Moreover, it is preferable that the 2nd electrode 5 has the corrosion resistance with respect to electrolyte solution, and the liquid shielding property with respect to electrolyte solution. Thereby, corrosion of the photoelectric conversion part 2 by electrolyte solution can be prevented.
Although it will not specifically limit if the 2nd electrode 5 has electroconductivity, For example, it is a metal thin film, for example, is thin films, such as Al, Ag, Au. These can be formed by, for example, sputtering. Further, for example, a transparent conductive film such as In—Zn—O (IZO), In—Sn—O (ITO), ZnO—Al, Zn—Sn—O, and SnO ₂ is used.

7). First Conductive Part The first conductive part 9 can be provided in contact with the first electrode 4 and the second electrolysis electrode 7. By providing the first conductive portion 9, the first electrode 4 and the second electrolysis electrode 7 in contact with the light receiving surface of the photoelectric conversion portion 2 can be easily electrically connected.
Moreover, the 1st electroconductive part 9 may be provided in the contact hole which penetrates the photoelectric conversion part 2 like FIG. Thus, the current path between the light receiving surface of the photoelectric conversion unit 2 and the second electrolysis electrode 7 can be shortened, and the first gas and the second gas can be generated more efficiently. Moreover, the contact hole provided with the 1st electroconductive part 9 may have one or more, and may have a circular cross section.
Moreover, the 1st electroconductive part 9 may be provided so that the side surface of the photoelectric conversion part 2 may be covered like FIG.

  The material of the 1st electroconductive part 9 will not be restrict | limited especially if it has electroconductivity. A paste containing conductive particles, for example, a carbon paste, an Ag paste or the like applied by screen printing, an inkjet method, etc., dried or baked, a method of forming a film by a CVD method using a raw material gas, a PVD method, Examples thereof include a vapor deposition method, a sputtering method, a sol-gel method, and a method using an electrochemical redox reaction.

8). Insulating part The insulating part 11 can be provided in order to prevent the occurrence of leakage current. For example, when the first conductive portion 9 is provided in a contact hole penetrating the photoelectric conversion portion 2 as shown in FIGS. 4 and 14, the insulating portion 11 can be provided on the side wall of the contact hole.
Moreover, the insulating part 11 can be provided between the electrode 7 for 2nd electrolysis and the back surface of the photoelectric conversion part 2 like FIG. This can prevent a leak current from being generated between the second electrolysis electrode 7 and the back surface of the photoelectric conversion unit 2. In addition, when the photoelectric conversion unit 2 receives light as shown in FIGS. 19 and 20 and generates a potential difference between the first area and the second area on the back surface of the photoelectric conversion unit 2, the insulating unit 11 1 between the electrode 8 for electrolysis and the back surface of the photoelectric conversion unit 2, and between the second electrode for electrolysis 7 and the back surface of the photoelectric conversion unit 2, and the insulating unit 11 is provided on the first area and the second area. You may have an opening on it. Thereby, the electrons and holes formed by the photoelectric conversion unit 2 receiving light can be efficiently separated, and the photoelectric conversion efficiency can be further increased.
Moreover, it is preferable that the insulation part 11 has the corrosion resistance with respect to electrolyte solution, and the liquid shielding property with respect to electrolyte solution. Thereby, generation | occurrence | production of a leakage current can be prevented and corrosion of the photoelectric conversion part 2 by electrolyte solution can be prevented.

The insulating part 11 can be used regardless of an organic material or an inorganic material. For example, polyamide, polyimide, polyarylene, aromatic vinyl compound, fluorine polymer, acrylic polymer, vinylamide polymer, etc. Examples of organic polymers and inorganic materials include metal oxides such as Al ₂ O ₃ , SiO ₂ such as porous silica films, fluorine-added silicon oxide films (FSG), SiOC, HSQ (Hydrogen Silsesquioxane) films, SiN _x , It is possible to use a method of forming a film by dissolving silanol (Si (OH) ₄ ) in a solvent such as alcohol and applying and heating.

  As a method for forming the insulating portion 11, a film containing a paste containing an insulating material is applied by a screen printing method, an ink jet method, a spin coating method, etc., dried or baked, or a CVD method using a source gas is used. And a method using a PVD method, a vapor deposition method, a sputtering method, a sol-gel method, and the like.

9. Second Conductive Part, Third Conductive Part The second conductive part 29 can be provided between the insulating part 11 and the second electrolysis electrode 7 or between the insulating part 11 and the first electrolysis electrode 8. . By providing the second conductive portion 29, an electromotive force generated by receiving light by the photoelectric conversion portion 2 can be efficiently output to the first electrolysis electrode 8 or the second electrolysis electrode 7 and the ohmic cross is reduced. can do. The second conductive portion 29 can be provided, for example, as shown in FIGS.
The second conductive portion 29 preferably has corrosion resistance to the electrolytic solution and liquid shielding properties to the electrolytic solution. Thereby, an increase in ohmic resistance can be prevented, and corrosion of the photoelectric conversion unit 2 due to the electrolytic solution can be prevented.
The 3rd electroconductive part 33 can be provided so that a photoelectric converting layer may be connected in series like FIG.

The second conductive portion 29 or the third conductive portion 33 is not particularly limited as long as it has conductivity. For example, the second conductive portion 29 or the third conductive portion 33 is a metal thin film, for example, a thin film such as Al, Ag, or Au. These can be formed by, for example, sputtering. Further, for example, a transparent conductive film such as In—Zn—O (IZO), In—Sn—O (ITO), ZnO—Al, Zn—Sn—O, and SnO ₂ is used.

10. First Electrolysis Electrode, Second Electrolysis Electrode The first electrolysis electrode 8 and the second electrolysis electrode 7 are provided on the back side of the photoelectric conversion unit 2, respectively. As shown in FIG. 4, the first and second electrolysis electrodes 8 and 7 may be provided on the back surface of the photoelectric conversion unit 2. Moreover, the electrode 8 for 1st electrolysis and the electrode 7 for 2nd electrolysis can each have the surface of the back surface side of the photoelectric conversion part 2, and the surface which is the back surface and can contact electrolyte solution. Thus, the first electrolysis electrode 8 and the second electrolysis electrode 7 do not block light incident on the photoelectric conversion unit 2.
In addition, when the first electrolysis electrode 8 and the second electrolysis electrode 7 are in contact with the electrolytic solution, the electrolysis solution is electrolyzed by using the electromotive force generated by the photoelectric conversion unit 2 receiving light, and the first gas is obtained. And the second gas can be generated. For example, when an electromotive force is generated between the light receiving surface and the back surface thereof when the photoelectric conversion unit 2 receives light, the first electrolysis electrode 8 is connected to the back surface of the photoelectric conversion unit 2 as shown in FIGS. The second electrolysis electrode 7 can be electrically connected to the light receiving surface of the photoelectric conversion unit 2. Further, when an electromotive force is generated between the first area and the second area on the back surface of the photoelectric conversion unit 2 by receiving light, the first electrolysis electrode 8 is connected to the first area and the second area as shown in FIGS. The second electrolysis electrode 7 can be electrically connected to the other of the first area and the second area.

  14 and 15, when the first electrolysis electrode 8 is not in contact with the back surface of the photoelectric conversion unit 2 or the second electrode 5, the first electrolysis electrode 8 is connected to the photoelectric conversion unit 2 via the switching unit 10. It can be electrically connected to the back surface of. 13, 15, and 18, the second electrolysis electrode 7 can be electrically connected to the light receiving surface of the photoelectric conversion unit 2 via the switching unit 10.

At least one of the first electrolysis electrode 8 and the second electrolysis electrode 7 may be plural, and each may have a surface that can contact the strip-shaped electrolyte solution, and the long sides of the surfaces are adjacent to each other. Alternatively, they may be provided alternately. In this way, by providing the first electrolysis electrode 8 and the second electrolysis electrode 7, the distance between the portion where the reaction generating the first gas occurs and the portion where the reaction generating the second gas occurs is increased. It can be shortened, and the ion concentration imbalance generated in the electrolyte can be reduced. Moreover, the 1st gas and 2nd gas can be collect | recovered easily by making the surface which can contact electrolyte solution into strip | belt shape. For example, the first electrolysis electrode 8 and the second electrolysis electrode 7 can be provided as shown in FIG.
The first electrolysis electrode 8 and the second electrolysis electrode 7 preferably have corrosion resistance to the electrolytic solution and liquid shielding properties to the electrolytic solution. Thereby, the first gas and the second gas can be stably generated, and corrosion of the photoelectric conversion unit 2 due to the electrolytic solution can be prevented. For example, a metal plate or a metal film having corrosion resistance against the electrolytic solution can be used for the first electrolysis electrode 8 and the second electrolysis electrode 7.

Moreover, it is preferable that at least one of the first electrolysis electrode 8 and the second electrolysis electrode 7 has a catalyst surface area larger than the area of the light receiving surface of the photoelectric conversion unit 2. According to such a configuration, the first gas or the second gas can be generated more efficiently by the electromotive force generated in the photoelectric conversion unit 2.
In addition, at least one of the first electrolysis electrode 8 and the second electrolysis electrode 7 is preferably a porous conductor carrying a catalyst. According to such a configuration, the surface area of at least one of the first electrolysis electrode 8 and the second electrolysis electrode 7 can be increased, and the first gas or the second gas can be generated more efficiently. Can do. Further, by using a porous conductor, it is possible to suppress a change in potential due to a current flowing between the photoelectric conversion unit 2 and the catalyst, and to generate the first gas or the second gas more efficiently. Can be made. In this case, the first electrolysis electrode 8 or the second electrolysis electrode 7 can also have a two-layer structure of a portion having a liquid shielding property against the electrolytic solution and a porous portion.
One of the first electrolysis electrode 8 and the second electrolysis electrode 7 may be a hydrogen generation unit, and the other may be an oxygen generation unit. In this case, one of the first gas and the second gas is hydrogen, and the other is oxygen.

11. Hydrogen generating part The hydrogen generating part is a part for generating H ₂ from the electrolytic solution, and is one of the first electrolysis electrode 8 and the second electrolysis electrode 7.
Further, the hydrogen generation unit may include a catalyst for a reaction in which H ₂ is generated from the electrolytic solution. Thereby, the reaction rate of the reaction in which H ₂ is generated from the electrolytic solution can be increased. The hydrogen generation part may consist only of a catalyst for the reaction in which H ₂ is generated from the electrolytic solution, or this catalyst may be supported on a support. Further, the hydrogen generation unit may have a catalyst surface area larger than the area of the light receiving surface of the photoelectric conversion unit 2. Thereby, the reaction in which H ₂ is generated from the electrolytic solution can be set to a faster reaction rate. The hydrogen generation part may be a porous conductor carrying a catalyst. This can increase the catalyst surface area. In addition, a change in potential due to a current flowing between the light receiving surface or the back surface of the photoelectric conversion unit 2 and the catalyst included in the hydrogen generation unit can be suppressed. Furthermore, the hydrogen generation unit may include a hydrogen generation catalyst, and the hydrogen generation catalyst may include at least one of Pt, Ir, Ru, Pd, Rh, Au, Fe, Ni, and Se. According to such a configuration, hydrogen can be generated at a higher reaction rate by the electromotive force generated in the photoelectric conversion unit 2.

The catalyst for the reaction of generating H ₂ from the electrolyte (hydrogen generation catalyst) is a catalyst that promotes the conversion of two protons and two electrons into one molecule of hydrogen, is chemically stable, and generates hydrogen overvoltage. Can be used. For example, platinum group metals such as Pt, Ir, Ru, Pd, Rh, and Au, which have catalytic activity for hydrogen, and alloys or compounds thereof, Fe, Ni, and Se that constitute the active center of hydrogenase that is a hydrogen-producing enzyme. Alloys or compounds, and combinations thereof can be suitably used. Among them, a nanostructure containing Pt and Pt has a small hydrogen generation overvoltage and can be suitably used. Materials such as CdS, CdSe, ZnS, and ZrO ₂ whose hydrogen generation reaction is confirmed by light irradiation can also be used.

The hydrogen generating catalyst can be supported on the conductor. Examples of the conductor carrying the catalyst include metal materials, carbonaceous materials, and conductive inorganic materials.
As the metal material, a material having electronic conductivity and resistance to corrosion in an acidic atmosphere is preferable. Specifically, noble metals such as Au, Pt, Pd, metals such as Ti, Ta, W, Nb, Ni, Al, Cr, Ag, Cu, Zn, Su, Si, and nitrides and carbides of these metals, Examples of the alloy include stainless steel, Cu—Cr, Ni—Cr, and Ti—Pt. It is more preferable that the metal material contains at least one element selected from the group consisting of Pt, Ti, Au, Ag, Cu, Ni, and W from the viewpoint that there are few other chemical side reactions. These metal materials have a relatively small electric resistance, and can suppress a decrease in voltage even when a current is extracted in the surface direction. Further, when using a metal material having poor corrosion resistance in an acidic atmosphere such as Cu, Ag, Zn, etc., noble metals and metals having corrosion resistance such as Au, Pt, Pd, carbon, graphite, glassy carbon, A metal surface having poor corrosion resistance may be coated with a conductive polymer, a conductive nitride, a conductive carbide, a conductive oxide, or the like.

  As the carbonaceous material, a chemically stable and conductive material is preferable. Examples thereof include carbon powders and carbon fibers such as acetylene black, vulcan, ketjen black, furnace black, VGCF, carbon nanotube, carbon nanohorn, and fullerene.

Examples of the inorganic material having conductivity include In—Zn—O (IZO), In—Sn—O (ITO), ZnO—Al, Zn—Sn—O, SnO ₂ , and antimony oxide-doped tin oxide. .

  In addition, examples of the conductive polymer include polyacetylene, polythiophene, polyaniline, polypyrrole, polyparaphenylene, polyparaphenylene vinylene, and the like, and examples of the conductive nitride include carbon nitride, silicon nitride, gallium nitride, indium nitride, and nitride. Germanium, titanium nitride, zirconium nitride, thallium nitride, etc. are listed, and conductive carbides include tantalum carbide, silicon carbide, zirconium carbide, titanium carbide, molybdenum carbide, niobium carbide, iron carbide, nickel carbide, hafnium carbide, tungsten carbide. , Vanadium carbide, chromium carbide, and the like. Examples of the conductive oxide include tin oxide, indium tin oxide (ITO), and antimony oxide-doped tin oxide.

  The structure of the conductor supporting the hydrogen generation catalyst includes a plate shape, a foil shape, a rod shape, a mesh shape, a lath plate shape, a porous plate shape, a porous rod shape, a woven fabric shape, a nonwoven fabric shape, a fiber shape, and a felt shape. It can be used suitably. Further, a grooved conductor in which the surface of the felt-like electrode is pressure-bonded in a groove shape is preferable because the electric resistance and the flow resistance of the electrode liquid can be reduced.

12 Oxygen generating portion The oxygen generating portion is a portion that generates O ₂ from the electrolytic solution, and is one of the first electrolysis electrode 8 and the second electrolysis electrode 7.
Further, the oxygen generation unit may include a catalyst for a reaction in which O ₂ is generated from the electrolytic solution. Thereby, the reaction rate of the reaction in which O ₂ is generated from the electrolytic solution can be increased. Further, the oxygen generation part may consist only of a catalyst for the reaction that generates O ₂ from the electrolytic solution, or the catalyst may be supported on a carrier. Further, the oxygen generation unit may have a catalyst surface area larger than the area of the light receiving surface of the photoelectric conversion unit 2. Thereby, the reaction in which O ₂ is generated from the electrolytic solution can be set to a faster reaction rate. The oxygen generation part may be a porous conductor carrying a catalyst. This can increase the catalyst surface area. In addition, a change in potential due to a current flowing between the light receiving surface or the back surface of the photoelectric conversion unit 2 and the catalyst included in the oxygen generation unit can be suppressed. Furthermore, the oxygen generation unit may include an oxygen generation catalyst, and the oxygen generation catalyst may include at least one of Mn, Ca, Zn, Co, and Ir. According to such a configuration, oxygen can be generated at a higher reaction rate by the electromotive force generated in the photoelectric conversion unit.

The catalyst for the reaction of generating O ₂ from the electrolyte (oxygen generating catalyst) is a catalyst that promotes the conversion of two water molecules into one molecule of oxygen, four protons, and four electrons, and is chemically stable. In addition, a material having a small oxygen generation overvoltage can be used. For example, oxides or compounds containing Mn, Ca, Zn, Co, which are active centers of Photosystem II, which is an enzyme that catalyzes the reaction of generating oxygen from water using light, and platinum such as Pt, RuO ₂ , IrO ₂ It is possible to use compounds containing group metals, oxides or compounds containing transition metals such as Ti, Zr, Nb, Ta, W, Ce, Fe, Ni, and combinations of the above materials. Among these, iridium oxide, manganese oxide, cobalt oxide, and cobalt phosphate can be suitably used because they have low overvoltage and high oxygen generation efficiency.

The oxygen generating catalyst can be supported on the conductor. Examples of the conductor carrying the catalyst include metal materials, carbonaceous materials, and conductive inorganic materials. These explanations apply as long as there is no contradiction in the explanation of the hydrogen generation catalyst described in “11. Hydrogen generation section”.
When the catalytic activity of the hydrogen generating catalyst and the oxygen generating catalyst alone is small, a promoter can be used. Examples thereof include oxides or compounds of Ni, Cr, Rh, Mo, Co, and Se.

  The method for supporting the hydrogen generating catalyst and the oxygen generating catalyst can be applied directly to a conductor or semiconductor, PVD methods such as vacuum deposition, sputtering, and ion plating, dry coating methods such as CVD, The method can be appropriately changed depending on the material such as an analysis method. A conductive material can be appropriately supported between the photoelectric conversion unit and the catalyst. Also, when the catalytic activity for hydrogen generation and oxygen generation is not sufficient, the reaction surface area is increased by supporting it on porous materials such as metals and carbon, fibrous materials, nanoparticles, etc., and the hydrogen and oxygen generation rates are improved. It is possible to make it.

13. Back Substrate The back substrate 14 can be provided on the first electrolysis electrode 8 and the second electrolysis electrode 7 so as to face the translucent substrate 1.
The back substrate 14 can be provided such that a space is provided between the first electrolysis electrode 8 and the second electrolysis electrode 7 and the back substrate 14. This space can be used as the electrolytic solution chamber 15, and the first electrolytic electrode 8 and the second electrolytic electrode 7 can be brought into contact with the electrolytic solution by introducing the electrolytic solution into the electrolytic solution chamber 15. Moreover, when using a box-shaped thing for the back substrate 14, the back substrate 14 may be the bottom part of a box.

  Further, the back substrate 14 is a material that constitutes the electrolyte chamber 15 and confines the generated first gas and second gas, and a highly confidential substance is required. It is not particularly limited whether it is transparent or opaque, but it is preferably a transparent material in that it can be visually confirmed that the first gas and the second gas are generated. . The transparent back substrate is not particularly limited, and examples thereof include a transparent rigid material such as quartz glass, Pyrex (registered trademark), and a synthetic quartz plate, a transparent resin plate, and a transparent resin film. Among them, it is preferable to use a glass material because it is a gas that is not chemically permeable and is chemically and physically stable.

14 The partition wall 13 includes an electrolyte chamber 15 that is a space between the first electrolysis electrode 8 and the back substrate 14 and an electrolyte chamber 15 that is a space between the second electrolysis electrode 7 and the back substrate 14. It can be provided so as to partition. The partition wall 13 can also be provided between the first electrolysis electrode 8 and the second electrolysis electrode 7 as shown in FIG. When at least one of the first electrolysis electrode 8 and the second electrolysis electrode 7 is provided, the partition walls 13 can be provided so as to be arranged in parallel as shown in FIG. As a result, the first gas and the second gas generated by the first electrolysis electrode 8 and the second electrolysis electrode 7 can be prevented from mixing, and the first gas and the second gas can be separated. It can be recovered.
The partition wall 13 may include an ion exchanger. As a result, the ion concentration that is unbalanced by the electrolytic solution in the space between the first electrolysis electrode 8 and the back substrate 14 and the electrolytic solution in the space between the second electrolysis electrode 7 and the back substrate 14 is reduced. Can be kept constant.

For the partition wall 13, for example, an inorganic film such as porous glass, porous zirconia, or porous alumina or an ion exchanger can be used.
As the ion exchanger, any ion exchanger known in the art can be used, and a proton conductive membrane, a cation exchange membrane, an anion exchange membrane, or the like can be used.
The material of the proton conductive film is not particularly limited as long as it is a material having proton conductivity and electrical insulation, and a polymer film, an inorganic film, or a composite film can be used.

  Examples of the polymer membrane include Nafion (registered trademark) manufactured by DuPont, Aciplex (registered trademark) manufactured by Asahi Kasei Co., and Flemion (registered trademark) manufactured by Asahi Glass Co., Ltd., which are perfluorosulfonic acid electrolyte membranes. Examples thereof include membranes and hydrocarbon electrolyte membranes such as polystyrene sulfonic acid and sulfonated polyether ether ketone.

  Examples of the inorganic film include films made of phosphate glass, cesium hydrogen sulfate, polytungstophosphoric acid, ammonium polyphosphate, and the like. Examples of the composite membrane include a membrane made of a sulfonated polyimide polymer, a composite of an inorganic material such as tungstic acid and an organic material such as polyimide, and specifically, Gore Select membrane (registered trademark) or pores manufactured by Gore. Examples thereof include a filling electrolyte membrane. Furthermore, when used in a high temperature environment (for example, 100 ° C. or higher), sulfonated polyimide, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), sulfonated polybenzimidazole, phosphonated polybenzimidazole, sulfuric acid. Examples include cesium hydrogen and ammonium polyphosphate.

The cation exchange membrane may be any solid polymer electrolyte that can move cations. Specifically, fluorine ion exchange membranes such as perfluorocarbon sulfonic acid membranes and perfluorocarbon carboxylic acid membranes, polybenzimidazole membranes impregnated with phosphoric acid, polystyrene sulfonic acid membranes, sulfonated styrene / vinylbenzene copolymers Examples include membranes.
When the anion transport number of the supporting electrolyte solution is high, it is preferable to use an anion exchange membrane. As the anion exchange membrane, a solid polymer electrolyte capable of transferring anions can be used. Specifically, a polyorthophenylenediamine film, a fluorine-based ion exchange film having an ammonium salt derivative group, a vinylbenzene polymer film having an ammonium salt derivative group, a film obtained by aminating a chloromethylstyrene / vinylbenzene copolymer, etc. Can be mentioned.

15. Seal material The seal material 16 is a material for adhering the translucent substrate 1 and the back substrate 14 and sealing the electrolyte in the hydrogen production module 6 and the first gas and the second gas generated in the hydrogen production module 6. It is. When a box-shaped substrate is used for the back substrate 14, a sealing material 16 is used to bond the box and the translucent substrate 1. As the sealing material 16, for example, an ultraviolet curable adhesive, a thermosetting adhesive, or the like is preferably used, but the type thereof is not limited. The UV curable adhesive is a resin that undergoes polymerization upon irradiation with light having a wavelength of 200 to 400 nm and undergoes a curing reaction within a few seconds after light irradiation, and is divided into a radical polymerization type and a cationic polymerization type. Examples of the polymerization type resin include acrylates, unsaturated polyesters, and examples of the cationic polymerization type include epoxy, oxetane, and vinyl ether. Examples of the thermosetting polymer adhesive include organic resins such as phenol resin, epoxy resin, melamine resin, urea resin, and thermosetting polyimide. The thermosetting polymer adhesive is heated and polymerized in a state where pressure is applied at the time of thermocompression bonding, and then cooled to room temperature while being pressurized. I don't need it. In addition to the organic resin, a hybrid material having high adhesion to the glass substrate can be used. By using a hybrid material, mechanical properties such as elastic modulus and hardness are improved, and heat resistance and chemical resistance are dramatically improved. The hybrid material is composed of inorganic colloidal particles and an organic binder resin. For example, what is comprised from inorganic colloidal particles, such as a silica, and organic binder resin, such as an epoxy resin, a polyurethane acrylate resin, and a polyester acrylate resin, is mentioned.

  Here, the sealing material 16 is described. However, the sealing material 16 is not limited as long as it has a function of adhering the translucent substrate 1 and the back substrate 14, and a member such as a screw is externally used using a resin or metal gasket. It is also possible to appropriately use a method of applying pressure physically to increase confidentiality.

16. Electrolyte Chamber The electrolyte chamber 15 can be a space between the first electrolysis electrode 8 and the back substrate 14 and a space between the second electrolysis electrode 7 and the back substrate 14. Further, the electrolyte chamber 15 can be partitioned by the partition wall 13.

17. Water supply port, water supply pipe The water supply port 18 can be provided by making an opening in a part of the sealing material 16 included in the hydrogen production module 6 or a part of the back substrate 14. The water supply port 18 is arranged to replenish the electrolytic solution that has been decomposed into the first gas and the second gas, and the arrangement location and shape of the water supply port 18 are such that the raw electrolyte is efficiently supplied to the hydrogen production module 6. If it does, it will not be limited in particular.

  Further, the water supply port 18 can be connected to the water supply pipe 24, and the water supply port 18 and the water supply pipe 24 can be electrically connected. As a result, the electrolytic solution can be supplied to the hydrogen production module 6 through the water supply pipe 24. Further, the water supply pipe 24 can be provided so as to be removable from the water supply port 18. Thereby, the water supply pipe 24 can be removed from the hydrogen production module 6 and the hydrogen production apparatus 21 can be transformed from the first form to the second form. When the hydrogen production apparatus 21 has a plurality of hydrogen production modules 6, the water supply pipes 24 can be connected to the water supply ports of the respective hydrogen production modules 6, and the water supply pipes 24 can connect the plurality of hydrogen production modules 6. The water supply pipe 24 can be used as the connecting portion 12.

  Further, the water supply port 18 and the water supply pipe 24 can have a liquid leakage prevention mechanism. Thus, when the hydrogen production apparatus 21 is deformed from the first form to the second form, leakage of the electrolyte can be minimized even if the water supply pipe 24 is detached from the water supply port 18. The liquid leakage prevention mechanism may be composed of, for example, a backflow prevention valve including a spring and a valve body, or may be composed of a marble check valve.

18. The first gas exhaust port, the second gas exhaust port, the first gas exhaust tube and the second gas exhaust tube The first gas exhaust port 20 and the second gas exhaust port 19 are the end portion of the first electrolysis electrode 8 and the second gas exhaust port. It can be provided close to the end of the electrode 7 for electrolysis. Thereby, the first gas can be recovered from the first gas discharge port 20, and the second gas can be recovered from the second gas discharge port 19.

Further, the first gas discharge port 20 contacts the electrolytic solution of the first electrolysis electrode 8 when the hydrogen generator 21 of the first form is installed so that the light receiving surface of the photoelectric conversion unit 2 is inclined with respect to the horizontal plane. It can be provided close to the upper end of the possible surface. The second gas discharge port 19 contacts the electrolytic solution of the second electrolysis electrode 7 when the hydrogen production device 21 of the first form is installed so that the light receiving surface of the photoelectric conversion unit 2 is inclined with respect to the horizontal plane. It can be provided close to the upper end of the possible surface. Thus, when the hydrogen production device 21 of the first embodiment is installed such that the light receiving surface of the photoelectric conversion unit 2 is inclined with respect to the horizontal plane, and sunlight is incident on the light receiving surface, the first electrolysis electrode The first gas generated in 8 can be raised as bubbles in the electrolytic solution and recovered from the first gas discharge port 20, and the second gas generated in the second electrolysis electrode 7 can be recovered as bubbles in the electrolytic solution. It can be raised and recovered from the second gas outlet 19.
The 1st gas exhaust port 20 and the 2nd gas exhaust port 19 can be formed by providing opening in the sealing material 16, for example. An inflow prevention valve may be provided so that the electrolyte does not flow into the first gas outlet 20 and the second gas outlet 19.

Further, the first gas discharge port 20 can be connected to and connected to the first gas discharge tube 22, and the second gas discharge port 19 can be connected to and connected to the second gas discharge tube 23.
Moreover, the 1st gas exhaust pipe 22 and the 2nd gas exhaust pipe 23 can be provided so that it can remove from the 1st gas exhaust port 20 and the 2nd gas exhaust port 19, respectively. Thereby, the 1st gas exhaust pipe 22 and the 2nd gas exhaust pipe 23 can be removed from the hydrogen production module 6, and the hydrogen production apparatus 21 can be changed from a 1st form to a 2nd form. When the hydrogen production apparatus 21 has a plurality of hydrogen production modules 6, the first gas exhaust pipe 22 and the second gas exhaust pipe 23 are respectively connected to the first gas exhaust port 20 and the second gas exhaust pipe of each hydrogen production module 6. The first gas discharge pipe 22 and the second gas discharge pipe 23 can be connected to the plurality of hydrogen production modules 6, and the first gas discharge pipe 22 or the second gas discharge pipe 23 can be connected to the outlet 19. It can also be set as the connection part 12.

  Moreover, the 1st gas exhaust port 20 and the 2nd gas exhaust port 19 can have a liquid leak prevention mechanism. Thus, when the hydrogen production apparatus 21 is deformed from the first form to the second form, the first gas discharge pipe 22 and the second gas discharge pipe 23 are respectively connected from the first gas discharge port 20 and the second gas discharge port 19. Even if it is removed, leakage of the electrolyte can be prevented. The liquid leakage prevention mechanism may be composed of, for example, a backflow prevention valve including a spring and a valve body, or may be composed of a marble check valve.

19. Electrolytic Solution The electrolytic solution is not particularly limited as long as it is a raw material for the first gas and the second gas. For example, the electrolytic solution is an aqueous solution containing an electrolyte, for example, an electrolytic solution containing 0.1 M H ₂ SO ₄ , 0.1M potassium phosphate buffer. In this case, hydrogen and oxygen can be produced from the electrolytic solution as the first gas and the second gas.

20. Switching Unit The hydrogen production device 21 or the hydrogen production module 6 can have a switching unit 10. The switching unit 10 outputs the electromotive force generated when the photoelectric conversion unit 2 receives light to the first external circuit and the electromotive force generated when the photoelectric conversion unit 2 receives light from the first electrolysis electrode 8 and the second electrode. It is possible to switch between a circuit that outputs to the electrode 7 for electrolysis and generates a first gas and a second gas from the electrolyte. Thus, when the hydrogen production apparatus 21 is in the first form and light is incident on the photoelectric conversion unit 2 of the hydrogen production module 6, the electromotive force generated by the photoelectric conversion unit 2 receiving light is supplied to the first external circuit. In addition, the first gas and the second gas can be produced using the electromotive force generated when the photoelectric conversion unit 2 receives light.
The method for electrically connecting the switching unit 10 to the first external circuit is not particularly limited. For example, even if the switching unit 10 includes an output terminal and is electrically connected to the first external circuit via the output terminal. Good.

The switching unit 10 can be electrically connected to the second external circuit, and outputs an electromotive force input from the second external circuit to the first electrolysis electrode 8 and the second electrolysis electrode 7. It can switch to the circuit which produces | generates 1st gas and 2nd gas, respectively from electrolyte solution. Thus, the first gas and the second gas can be produced from the electrolyte using the electromotive force input from the second external circuit. Whether the hydrogen production apparatus 21 is in the first form or the second form, the first gas and the second gas can be produced using the electromotive force input from the second external circuit. However, by using the electromotive force input from the second external circuit with the hydrogen production device 21 as the second configuration, the piping distance between the first gas and the second gas can be reduced by producing the first gas and the second gas. The first gas and the second gas can be efficiently recovered.
The method for electrically connecting the switching unit 10 to the second external circuit is not particularly limited. For example, the switching unit 10 may include an input terminal and be electrically connected to the second external circuit via the input terminal. .

  This will be specifically described with reference to the drawings. 21 to 24 are schematic circuit diagrams of the hydrogen production apparatus of the present embodiment. 21 to 24 are schematic circuit diagrams in the case where the hydrogen production apparatus 21 has one hydrogen production module 6, but when the hydrogen production apparatus 21 has a plurality of hydrogen production modules 6, each hydrogen production module 6 The first electrode 4 and the second electrode 5 may be connected in parallel or in series, and the first electrolysis electrode 8 and the second electrolysis electrode 7 of each hydrogen production module 6 may be connected in parallel.

For example, when the hydrogen production module 6 has a cross section as shown in FIG. 15 and an electric circuit as shown in FIG. 21, for example, SW (switch) 1 and SW2 are in the ON state, and SW3 and SW4 are in the OFF state. In some cases, an electromotive force generated when the photoelectric conversion unit 2 receives light can be output to the first external circuit. Further, when SW1, SW2, SW5, and SW6 are in the OFF state and SW3 and SW4 are in the ON state, the electromotive force generated when the photoelectric conversion unit 2 receives light is used as the first electrolysis electrode 8 and the second electrolysis electrode. 7 can be output.
For example, when SW3 and SW4 are in an OFF state and SW5 and SW6 are in an ON state, an electromotive force input from the second external circuit is output to the first electrolysis electrode 8 and the second electrolysis electrode 7. be able to. When SW1 and SW2 are in the OFF state and SW3, SW4, SW5, and SW6 are in the ON state, both the electromotive force generated by the photoelectric conversion unit 2 receiving light and the electromotive force input from the second external circuit Can be output to the first electrolysis electrode 8 and the second electrolysis electrode 7.

For example, when the hydrogen production module 6 has a cross section as shown in FIGS. 13 and 18 and an electric circuit as shown in FIG. 22, for example, SW1 and SW2 are in an ON state, and SW3 and SW4 are in an OFF state. The electromotive force generated when the photoelectric conversion unit 2 receives light can be output to the first external circuit. Further, when SW1, SW2, SW3, and SW5 are in the OFF state and SW4 is in the ON state, the electromotive force generated by the photoelectric conversion unit 2 receiving light is applied to the first electrolysis electrode 8 and the second electrolysis electrode 7. Can be output.
For example, when SW1, SW2, and SW4 are in an OFF state and SW3 and SW5 are in an ON state, an electromotive force input from the second external circuit is applied to the first electrolysis electrode 8 and the second electrolysis electrode 7. Can be output. When SW1 and SW2 are in the OFF state and SW3, SW4 and SW5 are in the ON state, both the electromotive force generated when the photoelectric conversion unit 2 receives light and the electromotive force input from the second external circuit are It can output to the electrode 8 for 1 electrolysis and the electrode 7 for 2nd electrolysis.

For example, when the hydrogen production module 6 of this embodiment has a cross section as shown in FIG. 14 and an electric circuit as shown in FIG. 23, for example, SW1 and SW2 are in an ON state, and SW3 and SW4 are in an OFF state. In some cases, an electromotive force generated when the photoelectric conversion unit 2 receives light can be output to the first external circuit. Further, when SW1, SW2, SW3, and SW5 are in the OFF state and SW4 is in the ON state, the electromotive force generated by the photoelectric conversion unit 2 receiving light is applied to the first electrolysis electrode 8 and the second electrolysis electrode 7. Can be output.
For example, when SW1, SW2, and SW4 are in an OFF state and SW3 and SW5 are in an ON state, an electromotive force input from the second external circuit is applied to the first electrolysis electrode 8 and the second electrolysis electrode 7. Can be output. When SW1 and SW2 are in the OFF state and SW3, SW4 and SW5 are in the ON state, both the electromotive force generated when the photoelectric conversion unit 2 receives light and the electromotive force input from the second external circuit are It can output to the electrode 8 for 1 electrolysis and the electrode 7 for 2nd electrolysis.

For example, when the hydrogen production module 6 has cross sections as shown in FIGS. 4, 16, 17, 19, and 20 and has an electric circuit as shown in FIG. 24, for example, SW1 and SW2 are in an ON state, and SW3 and SW4 When the electromotive force generated by the photoelectric conversion unit receiving light does not reach the electrolytic voltage of the electrolytic solution, the electromotive force generated by the photoelectric conversion unit 2 receiving light is sent to the first external circuit. Can be output. In addition, when SW1, SW2, SW3, and SW4 are in the OFF state, and the electromotive force generated by the photoelectric conversion unit receiving light reaches the electrolytic voltage of the electrolytic solution, the photoelectric conversion unit 2 receives the light. The electromotive force can be output to the first electrolysis electrode 8 and the second electrolysis electrode 7. Therefore, even when the electric circuit as shown in FIG. 24 is provided, the switching unit 10 causes the photoelectric conversion unit 2 to receive the electromotive force generated by the photoelectric conversion unit 2 receiving light and the photoelectric conversion unit 2 to receive light. It is possible to switch between the circuit that outputs the electromotive force generated by the above to the first electrolysis electrode 8 and the second electrolysis electrode 7.
When SW3 and SW4 are in the ON state and SW1 and SW2 are in the OFF state, the electromotive force input from the second external circuit or the electromotive force input from the second external circuit and the photoelectric conversion unit 2 receive light. Both the electromotive forces generated by this can be output to the first electrolysis electrode 8 and the second electrolysis electrode 7.

The switching unit 10 can input information from the control unit, and can switch circuits based on the input information. Thereby, the switching unit 10 can switch to the circuit selected by the control unit.
The switching unit 10 can also switch circuits based on the magnitude of the electromotive force generated when the photoelectric conversion unit 2 receives light. As a result, when the electric power output to the first external circuit is generated in the photoelectric conversion unit 2, the electromotive force generated in the photoelectric conversion unit 2 can be output to the first external circuit and output to the first external circuit. When the power to be generated is not generated in the photoelectric conversion unit 2, the electromotive force generated in the photoelectric conversion unit 2 can be output to the first electrolysis electrode 8 and the second electrolysis electrode 7.
Furthermore, the switching unit 10 can also switch the circuit based on the magnitude of the electromotive force of the second external circuit. Thereby, when the electric power supplied from the second external circuit is larger than the electric demand, the first gas and the second gas can be produced using the electric power supplied from the second external circuit.

Hydrogen production method In the hydrogen production method of the present embodiment, the hydrogen production apparatus 21 of the first embodiment is installed so that the light receiving surface of the photoelectric conversion unit 2 is inclined with respect to the horizontal plane, and the electrolytic solution is introduced into the electrolytic solution chamber 15, By making sunlight enter the light receiving surface of the photoelectric conversion unit 2, first gas and second gas are generated from the first electrolysis electrode 8 and the second electrolysis electrode 7, respectively, and the first gas outlet 20 and the second gas are generated. The first gas and the second gas can be discharged from the gas discharge port 19, respectively.
Thus, the first gas and the second gas can be produced, and hydrogen can be produced.

    1: Translucent substrate 2: Photoelectric conversion unit 4: First electrode 5: Second electrode 6, 6a, 6b, 6c, 6d: Hydrogen production module 7: Electrode for second electrolysis 8: Electrode for first electrolysis 9: 1st electroconductive part 10: Switching part 11: Insulating part 12: Connection part 13: Partition 14: Back substrate 15: Electrolyte chamber 16: Sealing material 18: Water supply port 19: 2nd gas exhaust port 20: 1st gas exhaust port 21: Hydrogen production apparatus 22: 1st gas discharge pipe 23: 2nd gas discharge pipe 24: Water supply pipe 25: Liquid leakage prevention mechanism 26: Hinge member 28: Photoelectric conversion layer 29: 2nd electroconductive part 30: Translucent electrode 31: Back electrode 33: Third conductive part 35: Semiconductor part 36: P-type semiconductor part 37: N-type semiconductor part 40: Isolation 46: Electrolytic solution 52: Wiring 54: Lumpur portion 55: guide groove 57: magnet part

Claims (14)

A hydrogen production apparatus that can be transformed from the first form to the second form or from the second form to the first form,
Comprising at least one hydrogen production module provided in a deformable manner,
The hydrogen production module includes a photoelectric conversion unit having a light receiving surface and a back surface, a first electrolysis electrode and a second electrolysis electrode provided on the back surface side of the photoelectric conversion unit,
The first and second electrolysis electrodes have an electromotive force generated when the photoelectric conversion unit receives light when light enters the light receiving surface of the photoelectric conversion unit and the first and second electrolysis electrodes come into contact with the electrolytic solution. Is provided so that the electrolyte can be electrolyzed to generate the first gas and the second gas, respectively,
Of the first gas and the second gas, one is hydrogen and the other is oxygen,
The first embodiment is a direct receivable form the entire sunlight of the light receiving surface included in the hydrogen generating device,
The second embodiment, on the light-receiving surface side or the back side of the photoelectric conversion portions included in one of the hydrogen production module, Ri forms der which the photoelectric conversion units included in the same or a different said hydrogen production module is located,
The photoelectric conversion unit generates an electromotive force between the light receiving surface and the back surface by receiving light,
The first electrolysis electrode is provided so as to be electrically connected to the back surface of the photoelectric conversion unit,
2. The hydrogen production apparatus according to claim 1, wherein the second electrolysis electrode is provided so as to be electrically connected to the light receiving surface of the photoelectric conversion unit . The hydrogen production module is plural,
The first form is a form in which the hydrogen production modules are arranged so that sunlight can enter the light receiving surface of the photoelectric conversion unit of each hydrogen production module,
The apparatus according to claim 1, wherein the second form is a form in which the hydrogen production modules are stacked.   The apparatus of Claim 2 further provided with the connection part which connects a some hydrogen production module.   The apparatus according to claim 3, wherein the connecting portion has a structure including a rotating shaft. The connecting portion has a guide groove,
The apparatus of claim 3, wherein at least one hydrogen production module slides along the guide groove.   4. The apparatus according to claim 3, wherein each of the hydrogen production modules is separable, and is connected by a first connecting portion in the first form and connected by a second connecting part in the second form.   The apparatus according to claim 6, wherein the first and second connecting parts are separable from each hydrogen production module. Each hydrogen production module includes a water supply port for supplying the electrolyte into the hydrogen production module, a first gas exhaust port for discharging the first gas, and a second gas exhaust port for discharging the second gas,
The device according to claim 1, wherein a liquid leakage prevention mechanism is provided at the water supply port, the first gas discharge port, or the second gas discharge port. The hydrogen production module is a flexible sheet that can be rolled up, and the first form is an expanded form of the sheet-like hydrogen production module,
The apparatus according to claim 1, wherein the second form is a form in which the sheet-like hydrogen production module is rolled up. A switching unit that can be electrically connected to the first external circuit;
The switching unit includes a circuit that outputs an electromotive force generated when the photoelectric conversion unit receives light to the first external circuit, and an electromotive force generated when the photoelectric conversion unit receives light to the first and second electrolysis electrodes. The device according to any one of claims 1 to 9, wherein the output circuit can be switched.   The switching unit can be electrically connected to the second external circuit, and outputs an electromotive force input from the second external circuit to the first electrolysis electrode and the second electrolysis electrode from the electrolyte. The apparatus of claim 10, wherein the apparatus can be switched to a circuit that generates a first gas and a second gas. The said hydrogen production module is an apparatus as described in any one of Claims 1-11 provided with an insulation part between the electrode for 2nd electrolysis and the back surface of the said photoelectric conversion part. The apparatus according to claim 12 , wherein the hydrogen production module includes a first electrode that contacts a light receiving surface of the photoelectric conversion unit. The hydrogen production apparatus according to any one of claims 1 to 13 is installed so that a light receiving surface of the photoelectric conversion unit is inclined with respect to a horizontal plane in the first form,
An electrolyte is introduced into the hydrogen production module from the lower part of the hydrogen production module, and sunlight is incident on the light receiving surface of the photoelectric conversion unit to thereby cause the first gas and the second electrolysis electrode to enter the first gas and A hydrogen production method in which a second gas is generated and the first gas and the second gas are discharged from an upper part of the hydrogen production module.