CN209735575U

CN209735575U - Photosynthetic reaction device

Info

Publication number: CN209735575U
Application number: CN201920206307.5U
Authority: CN
Inventors: 邢志伟; 杨文献; 龙军华; 李雪飞; 吴渊渊; 陆书龙; 边历峰
Original assignee: Suzhou Institute of Nano Tech and Nano Bionics of CAS
Current assignee: Suzhou Institute of Nano Tech and Nano Bionics of CAS
Priority date: 2019-02-18
Filing date: 2019-02-18
Publication date: 2019-12-06
Anticipated expiration: 2029-02-18

Abstract

The utility model discloses a photosynthetic response device, including the reaction tank, proton exchange membrane, oxidation electrode, reduction electrode and wire, proton exchange membrane locates in the reaction tank in order to separate the reaction tank for first groove and second groove, the bottom in first groove is located to oxidation electrode, the bottom in second groove is located to reduction electrode, oxidation electrode and reduction electrode pass through the wire and connect each other, oxidation electrode includes the metal level, photoelectric conversion device and electrode reaction layer, the metal level is connected with the wire, photoelectric conversion device and electrode reaction layer are stromatolite on the metal level according to the preface. The utility model provides the high utilization ratio of sunlight.

Description

Photosynthetic reaction device

Technical Field

The utility model relates to an artificial photosynthesis field especially relates to a photosynthetic response device.

Background

Environmental and energy problems have become global problems, and the development and utilization of carbon resources have just started compared with new energy sources such as solar energy, hydroenergy, wind energy, nuclear energy and the like. The artificial photosynthesis can convert solar energy into chemical energy, and can produce renewable pollution-free fuel and energy-containing substances with various purposes, thereby having very important significance for reducing carbon dioxide emission and developing and utilizing new energy sources.

At present, solar energy utilization mainly includes three modes of photo-thermal conversion, photoelectric conversion and photochemical conversion, wherein photosynthesis has been developed for billions of years, and has very excellent structural and functional characteristics and high energy conversion efficiency. Therefore, researchers have proposed the concept of artificial photosynthesis as early as 90 s in the 20 th century. The research on the photocatalytic performance of inorganic semiconductor materials dates back to 1972, and Fujishima and Honda, etc. found the Honda island effect: the single crystal electrode and the Pt electrode are connected and put into water, and water can be decomposed into oxygen and hydrogen under the irradiation of sunlight. The third-generation semiconductor material GaN is widely applied to semiconductor lighting and power devices, is a photocatalytic material which can simultaneously meet the conditions of carbon dioxide reduction and water molecule oxidation, and has much smaller electron affinity than the conventional oxide material for photocatalysis, so that the GaN-based photocatalytic material has a huge application prospect in the aspects of hydrogen production by light and carbon dioxide emission reduction.

Generally, the source of the light energy absorbed by the artificial photosynthesis reaction device is sunlight, but the wavelength band of the light which is absorbed and utilized by the oxidation electrode of the light reaction device adopting GaN is relatively single, so that the photosynthesis reaction device which absorbs light in various wavelength bands needs to be designed to improve the utilization rate of the sunlight.

SUMMERY OF THE UTILITY MODEL

In order to achieve the purpose, the utility model adopts the following technical proposal:

The utility model provides a photosynthetic reaction device, includes reaction tank, proton exchange membrane, oxidation electrode, reduction electrode and wire, proton exchange membrane locates in the reaction tank in order with the reaction tank separates for first groove and second groove, oxidation electrode locates the bottom of first groove, reduction electrode locates the bottom of second groove, oxidation electrode with reduction electrode passes through the wire is connected each other, oxidation electrode includes metal level, photoelectric conversion device and electrode reaction layer, the metal level with the wire is connected, photoelectric conversion device with electrode reaction layer according to the preface stromatolite in on the metal level.

Preferably, the electrode reaction layer includes an N-type substrate, a buffer layer, and a plurality of N-type GaN nanorods, the N-type substrate and the buffer layer are sequentially stacked on the photoelectric conversion device, and the N-type GaN nanorods are disposed on a surface of the buffer layer facing away from the N-type substrate.

Preferably, the photoelectric conversion device is composed of at least one single junction sub-cell including a lower contact layer, a back field layer, a base region, a reflective layer, a window layer, and an upper contact layer sequentially stacked on the metal layer.

Preferably, the electrode reaction layer further comprises InxGa1-xN (0 ≦ x ≦ 1) quantum dots disposed in the N-type GaN nano-pillars.

Preferably, the reduction electrode includes a metal rod connected to the lead wire and a catalyst layer provided on a surface of the metal rod.

Preferably, a voltage stabilizer is connected in series between the oxidation electrode and the reduction electrode.

Preferably, the photoelectric conversion device is constituted by a plurality of the single junction sub-cells, which are connected in a stacked manner in order of increasing or decreasing energy band gaps.

compared with the prior art, the utility model discloses in the metal level with photoelectric conversion device has additionally been set up between the electrode reaction layer, photoelectric conversion device comprises at least one unijunction sub-cell, makes photoelectric conversion device can absorb the remaining light that electrode reaction layer did not absorb to generate extra hole-electron pair, these extra photoproduction holes can be gathered electrode reaction layer's decomposition reaction of water on the surface and participation, thereby improved the decomposition reaction rate of water, improved the utilization ratio of sunlight.

Drawings

FIG. 1 is a schematic structural view of a photosynthetic reaction apparatus of the present invention;

Fig. 2 is a schematic structural diagram of the photoelectric conversion device of the present invention.

Detailed Description

in order to make the objects, technical solutions and advantages of the present invention clearer, the following detailed description of the embodiments of the present invention will be described with reference to the accompanying drawings. Examples of these preferred embodiments are illustrated in the accompanying drawings. The embodiments of the invention shown in the drawings and described in accordance with the same are merely exemplary and the invention is not limited to these embodiments.

It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and/or process steps that are closely related to the solution according to the invention are shown in the drawings, while other details that are not relevant to the invention are omitted.

The present embodiment provides a photosynthetic reaction apparatus including: reaction tank 1, proton exchange membrane 2, oxidation electrode 3, reduction electrode 4 and wire 5. The reaction tank 1 is preferably made of a corrosion-resistant transparent material such as: polymethyl methacrylate, polystyrene, polycarbonate, methyl methacrylate, glass, sapphire, and the like. An anti-reflection film layer can be further arranged on the outer side surface of the reaction tank 1 to improve the collection of sunlight.

As shown in fig. 1, the proton exchange membrane 2 is provided in the reaction tank 1 to divide the reaction tank 1 into a first tank 1a and a second tank 1 b. In order to clearly distinguish the first tank 1a from the second tank 1b, it is also possible to form the first tank 1a and the second tank 1b by embedding the proton exchange membrane 2 in a partition plate and disposing the partition plate in the reaction tank 1, as an example. The oxidation electrode 3 is disposed at the bottom of the first tank 1a, the reduction electrode 4 is disposed at the bottom of the second tank 1b, and the oxidation electrode 3 and the reduction electrode 4 are connected to each other by the wire 5. After the reaction solution is filled in the reaction tank 1, an oxidation reaction of water molecules occurs in the first tank 1a (i.e., at the oxidation electrode 3) to generate hydrogen ions (protons) and electrons, and the hydrogen ions are transferred into the second tank 1b through the proton exchange membrane 2 and then combined with the electrons transferred through the lead 5 to generate hydrogen gas (reduction reaction). Since the proton exchange membrane 2 prevents the mixing of the reaction liquids in the first tank 1a and the second tank 1b, the chemical reactions at both sides do not interfere with each other, thereby improving the stability of the photosynthetic reaction.

Referring to fig. 1, the oxidation electrode 3 of the present invention includes a metal layer 31, a photoelectric conversion device 32, and an electrode reaction layer 33. The metal layer 31 is connected to the lead 5 as a back electrode of the oxidation electrode 3. The electrode reaction layer 33 serves as a reaction portion of the oxidation electrode 3, and the electrode reaction layer 33 generates (receives light energy) hole-electron pairs in the light irradiation environment. As the electron is transferred to the second groove 1b along with the wire 5, the hole is recombined with the electron of the water molecule, and then the light energy is received to repeatedly generate a hole-electron pair, thereby continuously performing the water decomposition reaction. The electrode reaction layer 33 is usually made of GaN material, and can absorb a single light ray. Therefore, in the present invention, a photoelectric conversion device 32 is additionally disposed between the metal layer 31 and the electrode reaction layer 33.

As shown in fig. 2, the photoelectric conversion device 32 is composed of at least one single junction sub-cell a including a lower contact layer a1, a back field layer a2, a base region A3, a reflective layer a4, a window layer a5, and an upper contact layer a6, which are sequentially stacked on the metal layer 31. The photoelectric conversion device 32 can absorb the residual light not absorbed by the electrode reaction layer 33 to generate additional hole-electron pairs, and these additional photogenerated holes can be gathered on the surface of the electrode reaction layer 33 to increase the hole concentration, so that the water decomposition reaction rate is increased, and the utilization rate of sunlight is improved. It should be noted here that the photoelectric conversion device 32 is not in direct contact with the reaction liquid in the first trench 1a, and the main function of the photoelectric conversion device 32 is to provide additional holes to the electrode reaction layer 33, thereby increasing the decomposition rate of water.

In order to further improve the utilization rate of sunlight, the photoelectric conversion device 32 is configured by a plurality of the single junction sub-cells a, and the plurality of single junction sub-cells a are stacked and connected in order of increasing or decreasing energy band gaps. The energy band gap of each single-junction sub-cell a corresponds to different light bands of sunlight, so that the photoelectric conversion device 32 can absorb most of the sunlight energy, thereby improving the overall light utilization rate of the oxidation electrode 3.

Further, in order to provide the current density required by light and reaction, a voltage stabilizer 6 is connected in series between the oxidation electrode 3 and the reduction electrode 4, so that the current density of the lead 5 is maintained above 1.2mA/cm 2.

Further, in order to increase the reaction speed of water decomposition, the electrode reaction layer 33 includes an N-type substrate 33a, a buffer layer 33b, and a plurality of N-type GaN nanorods 33c, wherein the N-type substrate 33a and the buffer layer 33b are sequentially stacked on the photoelectric conversion device 32, the N-type GaN nanorods 33c are disposed on a surface of the buffer layer 33b facing away from the N-type substrate 33a, and the N-type GaN nanorods 33c are particularly in0.25ga0.75n nanorods. The plurality of N-type GaN nanorods 33c increase the surface area of the oxidation electrode 3, and increase the reaction rate of water decomposition to some extent. The surface of the N-type GaN nano column 33c can also be provided with a plurality of InxGa1-xN (x is more than or equal to 0 and less than or equal to 1) quantum dots with catalytic function, and the InxGa1-xN (x is more than or equal to 0 and less than or equal to 1) quantum dots can inhibit the self hole-electron recombination rate in the electrode reaction layer 33 and can keep the electrode reaction layer 33 in good oxidizability.

Further, the reduction electrode 4 includes a metal rod 41 and a catalyst layer 42, the metal rod 41 is connected to the lead 5, and the catalyst layer 42 is provided on a surface of the metal rod 41. The metal bar 41 and the catalyst layer 42 may be replaced accordingly according to the reduction reaction product in the second tank 1 b. As an example, the reduction reaction performed in the second tank 1b is a carbon dioxide reduction reaction in an illuminated environment, specifically, a reaction in which carbon dioxide is reduced in an illuminated environment to generate an organic small molecule compound such as formic acid or acetic acid (the hydrogen ions and electrons transferred from the first tank 1a also participate in the reduction reaction). In this example, the metal rod 41 is made of copper (corresponding electrode materials, such as gold, silver, platinum or a material with high conductivity and corrosion resistance, may also be selected according to product requirements), and the catalyst layer 42 is preferably a composite film of graphene and porphyrin. In order to achieve a better catalytic effect, a soluble catalyst corresponding to the catalyst layer 42 may be added to the reaction solution in the second tank 1 b. The soluble catalyst is preferably a mixed solution of graphene clusters and porphyrin.

The utility model discloses in additionally set up photoelectric conversion device between metal level and electrode reaction layer, photoelectric conversion device comprises at least one list knot subcell for photoelectric conversion device can absorb the remaining light that electrode reaction layer did not absorb, with the extra hole-electron pair of generation, these extra photoproduction holes can assemble on electrode reaction layer's the decomposition reaction of water and participation, thereby improved the decomposition reaction rate of water, improved the utilization ratio of sunlight.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A photosynthetic reaction device is characterized by comprising a reaction tank (1), a proton exchange membrane (2), an oxidation electrode (3), a reduction electrode (4) and a lead (5), the proton exchange membrane (2) is arranged in the reaction tank (1) to divide the reaction tank (1) into a first tank (1a) and a second tank (1b), the oxidation electrode (3) is arranged at the bottom of the first groove (1a), the reduction electrode (4) is arranged at the bottom of the second groove (1b), the oxidation electrode (3) and the reduction electrode (4) are connected to each other by the wire (5), the oxidation electrode (3) comprises a metal layer (31), a photoelectric conversion device (32) and an electrode reaction layer (33), the metal layer (31) is connected to the lead (5), and the photoelectric conversion device (32) and the electrode reaction layer (33) are sequentially stacked on the metal layer (31).

2. A photosynthetic reaction device according to claim 1 wherein the electrode reaction layer (33) comprises an N-type substrate (33a), a buffer layer (33b), and a plurality of N-type GaN nanopillars (33c), the N-type substrate (33a) and the buffer layer (33b) being sequentially laminated on the photoelectric conversion device (32), the N-type GaN nanopillars (33c) being disposed on a surface of the buffer layer (33b) facing away from the N-type substrate (33 a).

3. A photosynthetic reaction device according to claim 2 characterized in that the photoelectric conversion means (32) is constituted by at least one single junction sub-cell (a) comprising a lower contact layer (a1), a back field layer (a2), a base region (A3), a reflective layer (a4), a window layer (a5) and an upper contact layer (a6) laminated in this order on the metal layer (31).

4. A photosynthetic reaction device according to claim 2 or 3 characterized in that the electrode reaction layer (33) further includes InxGa1-xN (0 ≦ x ≦ 1) quantum dots disposed in the N-type GaN nanopillars (33 c).

5. A photosynthetic reaction device according to claim 4, characterized in that the reduction electrode (4) includes a metal rod (41) and a catalyst layer (42), the metal rod (41) being connected to the wire (5), the catalyst layer (42) being provided on a surface of the metal rod (41).

6. Photosynthetic reaction device according to claim 1, characterized in that a potentiostat (6) is connected in series between the oxidizing electrode (3) and the reducing electrode (4).

7. A photosynthetic reaction device according to claim 3 characterized in that the photoelectric conversion means (32) is composed of a plurality of the single-junction sub-cells (a) which are connected in a stacked manner in order of increasing or decreasing energy band gap.