KR100616678B1 - Micro fuel cell and method for manufacturing the same - Google Patents

Abstract

Provided are a micro fuel cell that can be mounted on a portable electronic device such as a mobile communication terminal (mobile phone) or a notebook computer, and a manufacturing method thereof.

The present invention provides a first and second substrates provided with a semiconductor process and supplied with air (oxygen) and fuel (hydrogen), and a plurality of through holes, electrodes provided on the substrates, and interposed between the electrodes. The electrolyte membrane, the catalyst means formed in the through-holes of the substrates, and the CO removal means or CO removal and hydrogen selection provided on the side of the substrate to which fuel is supplied to the first and second substrates to remove CO contained in the fuel. Provided is a micro fuel cell comprising a CO removal-hydrogen selective transmission means provided to enable permeation.

According to the present invention, a fuel cell coupled with a hydrogen generating reformer is provided in a microminiature by using a semiconductor process (MEMS) to facilitate the mounting of portable electronic devices, and safe operation of the battery is realized, in particular fuel The high-purity hydrogen is supplied while removing carbon monoxide (CO), which causes catalyst poisoning, before the battery is introduced, thereby improving the efficiency of the overall fuel cell.

Fuel Cell, Microminiature, Micro, Reformer, Platinum / Palladium Membrane, Membrane

Description

Micro Fuel Cell and Method for Manufacturing The Same

1 is a perspective view showing a micro fuel cell according to the present invention.

2 is a structural diagram showing a micro fuel cell of the present invention.

Figure 3 is a schematic diagram showing the manufacturing step of the first substrate portion on the air supply side in the ultra-compact fuel cell of the present invention.

Figure 4 is a schematic diagram showing the manufacturing step of the second substrate portion on the fuel supply side in the ultra-compact fuel cell of the present invention.

5 is a photograph showing an Al anodic oxide film (AAO template) of the CO removal-hydrogen selective transmission means of the present inventors micro fuel cell,

(a) is a photograph showing the lumbar flat state

(b) is a photograph showing the nano-sized pores.

Fig. 6 is a schematic plan view showing a wafer-shaped manufacturing state of the present invention ultra fuel cell.

7 is a structural diagram showing a state including the terminal electrode portion of the ultra-compact fuel cell of the present invention.

8 is a structural diagram showing a combined state of the present inventors ultra-compact fuel cell and the reformer

Explanation of symbols on the main parts of the drawings

1 .... Subminiature Fuel Cell 10,30 .... Substrate

12,32 .... through hole 50a, 50b ... electrode

70 .... electrolyte membrane 90 ... catalyst means

110 .... CO removal means or CO removal-hydrogen selective transmission means

112 .... Al Anodized Aluminum Oxide Template

114 .... Inner pore of AAO membrane 116 .... Platinum or platinum-palladium

130 .... Hydrogen Reformer 132 .... Fuel Supply Port

134 ... heating means 136 casing member

138 .... Porous Ceramic 140 .... Platinum Membrane

142 .... palladium membrane

The present invention relates to a micro fuel cell that can be mounted on a portable electronic device such as a mobile communication terminal (mobile phone) or a notebook, and a method of manufacturing the same. It provides a very small size by using 'to facilitate the mounting of portable electronic devices, while safe operation is implemented, in particular, an Al Anodized Aluminum Oxide Template (Anodic Aluminum Oxide Template) (hereinafter, Ultra-compact fuel cell and its manufacture which effectively removes carbon monoxide (hereinafter referred to as 'CO') contained in fuel supplied by 'AAO membrane' and improves overall fuel cell efficiency by supplying higher purity hydrogen It is about a method.

With the depletion of modern energy and environmental issues, the development of fuel cells with high energy efficiency and low environmental pollution has been intensively developed. Such fuel cells can directly oxidize fuel such as hydrogen to generate electricity. It generates an environmentally friendly advantage that the noise is very low during operation and there is little pollution.

In addition, a fuel cell is defined as a cell (cell) having the capability of producing direct current by converting chemical energy of fuel (hydrogen) directly into electrical energy. Unlike conventional cells, fuel cells continuously supply fuel and air from outside. There is a difference in producing electricity.

In other words, the basic concept of a fuel cell is the use of electrons generated by the reaction of hydrogen and oxygen, for example, hydrogen passes through the anode and oxygen passes through the cathode, where hydrogen is electrochemically Reacts with oxygen to generate water while generating current at the electrode.

On the other hand, since direct current is generated while electrons pass through the electrolyte (membrane), heat is additionally produced, and the direct current is used as a power source of a direct current motor or is converted into an alternating current by an inverter and generated in a fuel cell. Heat can also be used as a steam for reforming or as heat for cooling and heating, which is also useful in terms of heat recycling compared to conventional lithium ion batteries.

In addition, the fuel of the fuel cell uses hydrogen generated through a reforming process using pure hydrogen or hydrocarbons such as methanol, and the reformer used for such reforming is a fuel cell (specifically, a power generation cell) of the present invention. Used in conjunction with one fuel cell system.

On the other hand, the oxygen supplied to the fuel cell makes it possible to increase the efficiency of the fuel cell as the pure oxygen, but it is accompanied by a number of problems associated with the actual oxygen storage, it is directly using the air containing a lot of oxygen, such a fuel cell The reaction of

Anode: H _2- > 2H + + 2e-,

Cathode: O ₂ + 2H + + 2e--> H ₂ O

Overall: H ₂ + O _2- > H ₂ O + Current + Heat

At this time, the electrolyte (membrane), which is an electron transfer medium interposed between the anode and the cathode, serves to enable hydrogen ions to move from one electrode to the other electrode. It is most desirable that both electrodes (anode / cathode) be provided as thin as possible in order not to contact each other in order to minimize the resistance of the transfer.

Meanwhile, the fuel cells described so far can be classified into various forms as shown in Tables 1 and 2 below. Basically, there is no significant difference in the principle of operation, but only differences in fuel type, operating temperature, catalyst and electrolyte, etc. There is.

At this time, the various types of fuel cells described in the following Tables 1 and 2 include phosphate acid fuel cells (PAFC), alkaline fuel cells (AFC), and polymer electrolyte fuel cells (Proton). Exchange Membrane Fuel Cell (PEMFC), Molten Carbonate Fuel Cell (MCFC), Solid Oxide Fuel Cell (SOFC), and Direct Methanol Fuel Cell (DMFC) and the like, and when describing fuel cells by type in the following, they are abbreviated in English.

Classification of fuel cell by electrolyte, catalyst and operating temperature Kinds Ex harm catalyst Driving temperature PAFC Phosphoric Acid (Liquid) platinum on PTFE / carbon 200 ℃ AFC Potassium Hydroxide (Liquid) platinum on carbon 80 ℃ PEMFC Nafion Dow Polymer platinum on carbon  85-100 ℃ MCFC Lithium or potassium carbonate (liquid) Nickel nickel compounds 650 ℃ SOFC Yttria-stabilized zirconia (solid) Nickel Zirconia cermet 1000 ℃ DMFC Polymer Membrane Pt-Ru Pt / C 25-130 ℃

Classification of fuel cells by main fuel  Kinds Power generation temperature Electrolyte Main fuel Technology level Applicable object    PEMFC DMFC Room temperature-100 ℃ Ion (H +) conductive polymer membrane Hydrogen methanol Development and demonstration stage Small power car PAFC  150-200 ℃ Phosphoric Acid (H3PO4) Natural Gas Methanol  Commercialization stage Distributed power MCFC 600-700 ℃ Molten Carbonate (Li2CO3-K2CO3) Natural Gas Coal Gas Development stage Combined Cycle Cogeneration SOFC 700-1000 ℃ Solid Oxides Yttria-stabilized zirconia Natural Gas Coal Gas Development stage Combined Cycle Cogeneration AFC Room temperature-100 ℃ Hydrogen in use Special purpose

Meanwhile, among the various types of fuel cells, the use of mobile communication terminals, notebook computers, or portable multi-counters (hereinafter, collectively referred to as 'portable electronic devices') is rapidly increasing. It is becoming.

For example, although the performance of secondary batteries such as lithium-ion batteries, which are commonly used, has been greatly improved compared to when they are mounted in early portable electronic devices, studies on mounting high-capacity and compact fuel cells have been conducted. It is concentrated.

On the other hand, among the various types of fuel cells described above, as the small (micro) fuel cells mounted on portable electronic devices, the most researched and practical fuel cells are DMFC and PEMFC (PEFC).

In this case, DMFC and PEMFC use methanol and hydrogen as fuels, respectively, and accordingly, the performance and fuel supply system of the fuel cell are different from each other, and have advantages and disadvantages.

However, since the DMFC is significantly lower than the PEMFC in terms of output density, it is being researched for power supply of portable electronic devices, but its actual utilization value is being lowered.

On the other hand, since PEMFC (PEFC) uses hydrogen as a fuel, it is necessary to use a reformer for reforming fuel such as methanol to hydrogen and supplying it to a fuel cell (power cell). Except for power density, it is known to be advantageous for power supply of portable electronic devices.

In addition, portable electronic devices such as laptops and mobile phones are required to improve functions and services, and to improve battery capacity (performance) for comfortable use, in order to cope with various network environments of current portable electronic devices.

For example, fuel cells used in portable electronic devices are the key to miniaturization, unlike automotive and home use, and to maintain the desired output stably while being miniaturized.

On the other hand, a micro fuel cell (micro fuel cell) is known in which a fuel cell is implemented on a Si substrate (wafer) through a MEMS process in order to mount a fuel cell in a portable electronic device.

For example, although not shown in a separate drawing, US Pat. No. 6,638,654 discloses a thin-film fuel cell having a high output density by integrating an electrolyte layer, an electrode, and micro flow channels in a Si substrate. have.

However, the thin film fuel cell of the US patent has a structure in which a hydrogen channel and an oxygen channel are formed at a portion where each electrode is positioned, and although miniaturized by using MEMS technology, the manufacturing process is complicated and practical. It is difficult.

Meanwhile, another conventional micro fuel cell is disclosed in US Patent Application Publication No. 2004/0197613 (2004.8.7), in which a porous channel is applied to a fuel cell using a MEMS process.

That is, it is a fuel cell having a flow path (channel) structure including a micro flow path (channel) while fabricating a porous silicon wafer, forming a selective transmission film, and separating the selective transmission membrane as a metal layer.

Therefore, the fuel cell of the U.S. Patent Publication also has a miniaturization using MEMS technology, but as a multi-channel structure as a whole, the structure is complicated and multi-layered, there is a limit to the miniaturization, the actual implementation is not easy.

Accordingly, there has been a need for a very small (micro) fuel cell in which a fuel cell is implemented on a wafer (substrate) using a MEMS process, in particular, further enabling CO removal and hydrogen purification.

The present invention is to solve the conventional problems as described above, while being used in combination with the reformer, in particular, by having a micro structure that implements a fuel cell using a MEMS process, mass production is possible, to achieve a safe operation It is a first object of the present invention to provide a micro fuel cell and a method of manufacturing the same, which makes it possible to facilitate mounting on a portable electronic device.

In addition, the CO removal and hydrogen selective permeation means of the AAO membrane coated with platinum and palladium on the inner pores are provided on the fuel inlet side, thereby effectively eliminating CO, which causes catalyst poisoning, and supplying purified water with high purity hydrogen. It is a second object of the present invention to provide an ultra-small fuel cell and a method of manufacturing the same, which are improved in efficiency and efficiency of a fuel cell by improving the output density of the overall fuel cell.

Finally, a third object is to provide an ultra-compact fuel cell and a method of manufacturing the same, which are capable of miniaturizing the entire fuel cell system and mounting a portable device in combination with the ultra-small reformer.

As a technical aspect of the present invention, the present invention provides a MEMS process comprising: first and second substrates provided with air (oxygen) and fuel (hydrogen) and having a plurality of through holes;

Electrodes provided on the substrates, respectively;

An electrolyte membrane interposed between the electrodes;

Catalytic means formed in the through-holes of the substrates; And,

A CO removal means provided to remove CO contained in the fuel, or a CO removal-hydrogen selective transmission means provided to enable CO removal and hydrogen selective transmission to the substrate side of the first and second substrates to which fuel is supplied;

It provides a micro fuel cell configured to include.

In still another aspect, the present invention provides a method for manufacturing a semiconductor device, the method including: preparing a first and a second substrate provided in a MEMS process and having through holes formed therein;

Providing an AAO film in which nanopores of CO removal-hydrogen selective transmission means are formed on a substrate side to which fuel (hydrogen) is supplied in the first and second substrates;

Forming an electrode on the substrate;

Forming catalyst means in the through-holes of the substrate;

Finally forming platinum and palladium on the surface of the inner nano pores of the AAO membrane or palladium on the pore surface and platinum on the surface of the AAO membrane to finally provide a CO removal-hydrogen permeation means; And,

High temperature bonding the first and second substrates through a polymer electrolyte membrane;

It provides a method of manufacturing a micro fuel cell comprising a.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

On the other hand, the ultra-compact fuel cell of the present invention described below is passive-PEMFC (see Table 2) using hydrogen as a main fuel having a power density of approximately 10 times higher than passive-DMFC (see Table 2). The reformer used in combination with the fuel cell of the present invention (130 in FIG. 8) is a reformer for reforming methanol fuel and supplying hydrogen.

First and Figure 1 and Figure 2 shows a micro fuel cell 1 according to the present invention in a perspective view and a structural diagram,

That is, as shown in Figure 2, the micro fuel cell 1 of the present invention is largely supplied with air, that is, oxygen and fuel, that is, hydrogen, and is provided in the MEMS process, a plurality of through holes 12, 32 Formed first and second substrates 10 and 30, electrodes 50a and 50b of respective anodes and cathodes provided on the first and second substrates 10 and 30, and the electrodes 50a. ) And the catalyst means 90 formed in the through-holes 12 and 32 of the first and second substrates 10 and 30, and the first and second electrolyte membranes 70 disposed between them. The two substrates are divided into CO removal means or CO removal-hydrogen selective transmission means 110 provided to any one of the substrates (actually the second substrate) to which hydrogen is supplied.

First, the fuel cell 1 of the present invention includes first and second substrates 10 and 30 having a plurality of through holes 12 and 32 serving as a battery frame. 2 substrates 10 and 20 correspond to upper and lower substrates based on FIGS. 1 and 2.

At this time, the first and second substrates 10 and 30 are each made of a Si material and are manufactured by a MEMS process, and a plurality of through holes 12 and 32 are formed in the catalyst means 90 to be described below. Are integrally formed through.

Meanwhile, the first and second substrates 10 and 30 of the present invention include substrate cutouts 14 and 34, which are shown in FIGS. 1 and 2. Likewise, it serves as an enclosure surrounding an area that allows air (oxygen) and hydrogen to be evenly supplied as fuel for generating an electric current.

The side opposite to the substrate of the substrate cutouts 14 and 34 is provided as a flat electrode forming surface.

On the other hand, the substrate cut-out portion 14, 34 as shown in the Figure is preferably in the form of widening toward the top as an inclined surface.

Next, the electrodes 50a and 50b which are anode and cathode, respectively, are formed on the flat surface of the first and second substrates 10 and 30 opposite the substrate cutouts. The electrode of the first substrate is a cathode, and the electrode of the second substrate to which hydrogen is supplied is an anode.

On the other hand, the electrode of the present invention can be formed on the flat surface of the substrate 10, 30 by the same material having excellent conductivity, for example, platinum (Pt) or gold (Au) by the sputtering process. .

Next, the catalyst means 90 provided in the through holes 12 and 32 of the first and second substrates 10 and 30 on which the electrodes 50a and 50b are respectively formed is platinum or a reaction area of the catalyst. It can be provided as a porous catalyst to promote the ionization of hydrogen by the oxidation reaction by coating platinum on the surface of the internal pores of the porous carbon to enlarge the.

In this case, in the case of the porous catalyst, since platinum is coated on the surfaces of the internal pores of the porous carbon, the catalytic reaction area in contact with air and hydrogen is increased, which will increase the integration degree of ionization and enable higher density output. .

In addition, as shown in Figures 1 and 2, the catalyst means 90 is preferably formed by filling the through holes 12, 32 of the first and second substrates 10, 30, which is a catalyst This is because the larger the area in which the means is in contact with air and hydrogen, the better the reduction reaction of hydrogen and oxygen. For this purpose, the catalytic means 90 of the present invention is a through hole of the first and second substrates 10 and 30. It is preferable to coat it evenly in (12) (32).

Next, as shown in FIGS. 1 and 2, an electrolyte membrane 70, which is an insulating material, is provided between the electrodes 50a and 50b of the substrates 10 and 30. The fuel cell of the present invention is described above. As described above, in consideration of passive-PEMFC, the electrolyte membrane 70 is formed of a solid polymer electrolyte membrane.

For example, the most commonly used Nafion Membrane manufactured by DuPont may be used.

On the other hand, such an electrolyte membrane 70 is also used as a medium for bonding the first and second substrates 10 and 30, the spray method on any one of the first and second substrates 10, 30 substrate electrode And the like, and the first and second substrates 10 and 30 are hot pressed while being heated at a high temperature, and are attached at a high temperature through the electrolyte membrane 70.

Meanwhile, in the micro fuel cell 1 manufactured by the MEMS process according to the present invention, as illustrated in FIG. 6, a plurality of fuel cells 1 may be fabricated on a wafer W in units of cells. This makes it possible to manufacture microfuel cells in large quantities.

Next, as shown in FIG. 2, the CO cutting means or the CO removal-hydrogen selective transmission means 110 is provided in the substrate cutout 34 on the side of the second substrate 30 to which hydrogen is supplied.

That is, as described above, a small fuel cell for use in a portable electronic device mainly consists of DMFC and PEMFC using methanol aqueous solution or hydrogen, and when using methanol aqueous solution (DMFC) without a separate reformer Methanol aqueous solution can be used, but the output density is low, so it is difficult to use.

Therefore, although PEMFC using hydrogen as a fuel has attracted attention for power supply of portable electronic devices, it is particularly problematic that CO contained in fuel (hydrogen) must be kept at least 50 ppm or less, which means that CO is a fuel cell. This is because the oxidation reaction catalyst of, for example, causes poisoning of the catalyst means 90.

Of course, the reformer (see 130 of FIG. 8) also removes such CO to supply hydrogen, but in the ultra-fuel fuel cell 1 of the present invention, the CO removal means or CO removal-hydrogen permeation means 110 is hydrogen. It will be possible to implement a high capacity fuel cell with improved efficiency, as it allows for the additional removal of CO in PEMFC using or with high purity hydrogen supply through hydrogen selective permeation.

At this time, the CO removal means or CO removal-hydrogen selective transmission means 110, as shown in Figure 2, on the substrate cutout portion 34 side of the second substrate 30 (lower substrate) to which hydrogen is supplied. Platinum 116 for CO removal on the surface of the provided AAO film 112 and the nanopores 114 therein, or deposited on the surface of the pores 114 in order to allow CO removal and hydrogen selective transmission. It may be made of platinum (Pt) and palladium (Pd) 116.

On the other hand, although the CO removal-hydrogen selective transmission means 110 is not shown separately in the drawing, palladium deposited on the surface of the AAO film 112 and the inner nano-pores 114 of the AAO film 112, It may be made of platinum deposited in the form of a membrane on the surface of the AAO film 112.

In this case, platinum provides a function of absorbing and removing CO, and the palladium provides a function of enabling selective permeation of hydrogen to enable higher purity hydrogen supply, and such platinum (Pt) and palladium (Pd) ) Function is known.

At this time, the AAO film 112 and the pores 114 therein of the CO removal means or CO removal-hydrogen selective transmission means 110 deposit aluminum on a substrate, and the primary anodizing and electropolishing process. Platinum (Pt) alone or platinum to remove the CO described above in the nano-sized pores 114 are formed in the alumina oxidized through the etching and the secondary anodized film treatment. Palladium (Pd) which purifies and hydrogen is provided in order by being deposited.

Therefore, the CO removal means or CO removal-hydrogen selective transmission means 110 of the present invention is characterized in that the AAO membrane 112 provided at its inlet is supplied before hydrogen, which is fuel, is supplied to the power generation side of the fuel cell, that is, the electrode and the electrolyte membrane side. Platinum or platinum and palladium deposited in the inner pores 114 to maximize the reaction area while reliably remove the CO poisoning cause of the catalytic means, or in addition to the higher purity hydrogen through selective permeation of hydrogen Since it is supplied, it is possible to make a very small and high efficiency output of a fuel cell.

In this case, the deposition of the pores 114 or the AAO film 112 of platinum and palladium will be described in detail in the following description of the manufacturing method.

Next, as shown in FIG. 7, when the first and second substrates 10 and 30 are attached to each other via the electrolyte membrane 70, the terminal electrode portions protruding to the opposite sides of the electrodes 50a and 50b. 50a 'and 50b', which are partially cut to protrude out of the substrate, and such terminal electrode portions 50a 'and 50b' are connected to external terminals to supply current. Let's do it.

Therefore, in the micro fuel cell 1 of the present invention described so far, the hydrogen ions of the fuel electrode are decomposed into hydrogen ions (H +) and electrons (e ^_ ) in the catalytic means 90, of which only hydrogen ions are selective. to pass through the polymer electrolyte membrane 70, and is transmitted to the side of the reduction electrode air electrode, at the same time, electronic (e ^_) is the electron (e ^_) move to the air electrode through an external wire (not shown), and takes place in this case The flow creates a current.

In addition, such a micro fuel cell of the present invention is not a complicated multi-cell stack and flow path structure as in the prior art, while enabling the miniaturization of the cell, it is operated at a temperature of less than 100 ° C. as a high output fuel cell having a large current density, Simple structure, quick start-up, response and excellent durability.

Next, FIG. 3 and FIG. 4 show manufacturing steps of the first substrate portion to which air (oxygen) is supplied and the second substrate portion to which fuel (hydrogen) is supplied in the micro fuel cell 1 of the present invention.

That is, as shown in FIG. 3, the substrate cutout 14 coats a photo register 10a on the back surface of the first substrate 10 provided through the MEMS process, and then after photolithography. It is formed integrally with the first substrate 10 through the wet, dry etching.

Next, a plurality of through-holes 12 are formed in the substrate, and a photo register 10b is coated on the flat surface side opposite to the incision of the Si substrate, photolithography is performed, and wet or dry. A plurality of through holes 12 are formed through etching.

Next, an electrode 50a is formed on the flat surface opposite to the substrate cutout of the first substrate 10. The electrode 50a may form platinum or gold having excellent electrical conductivity by a sputtering process. .

Finally, as shown in FIG. 3, a porous catalyst coated with platinum is formed on the surface of the internal means of the catalyst means 90, that is, platinum or porous carbon, in the through hole 12 of the first substrate 10. .

Therefore, the 1st board | substrate part 10 to which air is supplied in this state is ready.

Next, FIG. 4 illustrates a manufacturing step of the second substrate part 30 to which hydrogen is supplied. The substrate cutting part 34 and the through hole 32 and the platinum or porous material using the photoresists 30a and 30b are illustrated. Since the method of forming the catalyst means 90, which may be a catalyst, is the same as in FIG. 3, the description is omitted here.

Therefore, in the forming of the AAO film 112 provided on the substrate cutout 34 side of the second substrate 30 of the present invention, aluminum 112a is deposited on the substrate cutout 34 and electrolytically deposited. Electro-polishing, primary anodizing at 40V for 40 minutes with phosphorous acid, then etching (etching) through phosphorous and chromic acid, again at 40V for 6 minutes Secondary anodization.

Thus, an AAO film 112 of alumina is provided in which aluminum initially deposited on the substrate is oxidized and a plurality of nanopores 114 are formed therein.

That is, as illustrated in FIG. 6, nano-sized pores 114 are formed in the AAO film 112.

Next, through holes 32 are formed using the photoresist 30b and the electrode 50b is formed by the sputtering process, as shown in FIG. 3, and then the catalyst means 90 is coated, and finally, the AAO film ( Platinum is deposited on the surface of the inner nanopores 114 of 112 by known electroplating or atomic layer deposition (ALD), and then palladium is deposited in the same manner to about 2000-3000Å and finally 5000. While the AAO film formed of the membrane of about -6000 kPa and the CO removal-hydrogen selective transmission means 110 of the platinum + palladium 116 deposited in the inner pores thereof are integrally provided inside the substrate cutout on the hydrogen supply side, CO removal is, of course, to enable hydrogen purification.

At this time, since the internal pores of the AAO film 112 of the CO removal-hydrogen selective transmission means 110 are nano-fine pores in nano size, even if the platinum and palladium are deposited in sequence, the internal nano pores 114 of the AAO film are actually used. Since the deposited platinum and palladium are mixed on the surface of the field, it is possible to supply high purity hydrogen through hydrogen selective permeation while absorbing and removing CO in the fuel passing therethrough.

On the other hand, although not shown separately, in the CO removal-hydrogen selective transmission means 110, palladium having a hydrogen selective transmission function is deposited on the surface of the inner nano pores 114 of the AAO membrane 112 in the same manner as described above. In addition, a 2000-3000 mm thick platinum film (membrane) for depositing CO may be deposited on the surface of the AAO film 112 to provide a CO removal-hydrogen selective transmission means 110 of another type.

In addition, by depositing only platinum on the inner nanopores 114 of the AAO film 112, it may be provided as a CO removal means 110 for removing only CO.

Next, as shown in FIG. 2, the first and second mediators are formed through a Nafion Membrane 70, which is mainly used as a solid polymer electrolyte as an insulating means, between the first and second substrates 50a and 50b. When the substrates 10 and 30 are hot pressed, the micro fuel cell 1 of the present invention as shown in FIG. 2 is finally manufactured.

Meanwhile, as illustrated in FIG. 8, the fuel cell 1 of the present invention may be used in combination with a reformer 130 for reforming and supplying hydrogen.

That is, as shown in FIG. 8, the fuel cell 1 of the present invention generates hydrogen using a passive-PEMFC as a fuel, and supplies hydrogen to the fuel inlet side, which is a substrate cutout of the second substrate 30. The reformer 130 may be used in combination with the second substrate 30.

In this case, the reformer 130 used in the fuel cell of the present invention is implemented as a micro reformer, which is possible because the reformer is formed using a porous ceramic.

For example, the micro reformer 130 of the present invention includes a casing member 136 having a fuel supply port 132 and a fuel heating means 134, that is, a heating coil, and a casing member 10. The porous ceramic 138 coated with the hydrogen reforming catalyst 138b on the surfaces of the pores 138a formed therein, and sequentially stacked on the porous ceramic 138 to remove CO and discharge hydrogen of high purity. A CO removal platinum membrane 140 and a hydrogen selective permeation palladium membrane 142.

Therefore, the methanol supplied into the casing member 136 made of ceramic is heated by the heating means 134 and the vaporized methanol gas is coated with a hydrophobic catalyst coated on the surface of the inner pores 138a of the porous ceramic 138. 138b) For example, reformed with hydrogen while passing through a mixed catalyst of copper (Cu) and zinc oxide (ZnO) or additionally added alumina (Al ₂ O ₃ ) to maintain catalytic function and stabilize thermal properties do.

Next, CO which affects the poisoning of the catalyst means 90 of the fuel cell is removed while passing through the platinum membrane 140, and finally, purified hydrogen is passed through the palladium membrane 142 which is a hydrogen selective permeable membrane. The fuel cell 1 is supplied to the second substrate 30 side.

As a result, when the reformer 130 of the present invention is used, CO removal and high purity hydrogen are first supplied to the cutout portion 34 of the second substrate 30 of the fuel cell 1, and CO removal of the fuel cell is performed. Purified hydrogen is supplied to the catalytic means 90 provided in the substrate through hole 34 of the fuel cell as the CO is removed again through the platinum and palladium 116 of the hydrogen selective permeation means 110, where Ionization of hydrogen is activated, and poisoning of the catalytic means does not occur.

At this time, as shown in FIG. 8, the catalyst 138b coated on the surfaces of the internal pores 138a of the porous ceramic 138 is copper (Cu), zinc oxide (ZnO), which reforms fuel into hydrogen, and the mixed catalyst (138b1), and platinum (Pt) and alumina (Al ₂ O ₃₎ of porous ceramics (138) of one and separated by a CO removal catalyst mixture (138b2) for removing the CO of alumina (Al ₂ O ₃₎ Once formed with a height difference on the surface of the inner pores 138a, CO is further removed.

Accordingly, the fuel cell 1 combined with the micro reformer 130 of the present invention has a high output density, shorter start-up time for power generation, and miniaturization, so as to supply power for portable electronic devices. It is suitable for use and has good CO removal.

According to such a micro fuel cell of the present invention and a method of manufacturing the same, CO which is the poisoning cause of the catalyst affecting the fuel cell efficiency can be effectively removed.

Further, the fuel (hydrogen) supplied to the power generating portion side of the fuel cell by the hydrogen selective permeation means is more selectively purified.

Then, hydrogen passes through the porous catalyst having pores and the AAO membrane containing nanopores, thereby facilitating hydrogen purification and CO removal by expanding the catalytic reaction surface area, and enabling high output of hydrogen ionization.

Finally, with the use of AAO membranes on silicon wafers, an integrated fuel cell is provided and combined with the micro reformer coupled thereto, thereby providing various high-performance micro fuel cells that can be easily mounted on portable electronic devices. To provide them.

While the invention has been shown and described with respect to specific embodiments thereof, those skilled in the art can variously modify the invention without departing from the spirit and scope of the invention as set forth in the claims below. And that it can be changed. Nevertheless, it will be apparent that all such modifications and variations are included within the scope of the present invention.

Claims (17)

First and second substrates provided with a MEMS process and supplied with air (oxygen) and fuel (hydrogen) and having a plurality of through holes; Electrodes provided on the substrates, respectively; An electrolyte membrane interposed between the electrodes; Catalytic means formed in the through-holes of the substrates; And, A CO removal means provided to remove CO contained in the fuel, or a CO removal-hydrogen selective transmission means provided to enable CO removal and hydrogen selective transmission to the substrate side of the first and second substrates to which fuel is supplied; Micro fuel cell configured to include. The method of claim 1, The first and second substrates each include a silicon substrate to which air (oxygen) and fuel (hydrogen) are supplied, and further include a substrate cutout to enable uniform supply of air and fuel, and to provide the substrates. The electrode is a tiny fuel cell, characterized in that the platinum or gold. The method of claim 1, And the electrode includes a terminal electrode portion protruding out of the substrate to be provided as an external terminal. The method of claim 1, The electrolyte membrane is a very small fuel cell, characterized in that using the Nafion (Nafion) of the polymer electrolyte. The method of claim 1, The catalyst means formed in the through-holes of the substrate, the ultra-compact fuel cell, characterized in that consisting of a porous catalyst coated with platinum on the surface of the internal pores of the platinum catalyst or porous carbon. The method of claim 1, The CO removal means may include: an AAO membrane provided on the cutout side of the substrate to which fuel is supplied and in which nano pores are formed; And, Platinum (Pt) formed on the surface of the pores of the AAO film to remove CO contained in the fuel; Micro fuel cell, characterized in that consisting of. The method of claim 1, The CO removal-hydrogen selective transmission means comprises: an AAO film provided on the incision side of the substrate to which fuel (hydrogen) is supplied and in which nano pores are formed; And, Platinum (Pt) and palladium (Pd), which are sequentially formed on the surfaces of the pores of the AAO membrane, or are formed on the surfaces of the AAO membrane and the surfaces of the internal pores, respectively, to enable CO removal and selective permeation of hydrogen; Micro fuel cell, characterized in that consisting of. The method of claim 1, A casing member coupled to the fuel supply side substrate, the casing member having a fuel supply port and fuel heating means; Porous ceramic embedded in the casing member and the catalyst is coated on the surface of the pores formed therein; A platinum membrane and a palladium membrane which are sequentially stacked on top of the porous ceramic to remove CO and discharge high purity hydrogen; Micro fuel cell further comprises a reformer comprising a. The method of claim 8, The catalyst coated on the surface of the internal pores of the porous ceramic is a micro fuel cell, characterized in that composed of a mixed catalyst of copper (Cu) and zinc oxide (ZnO) to reform the fuel gas with hydrogen. The method of claim 8, The catalyst coated on the surface of the internal pores of the porous ceramic, the hydrophobic mixed catalyst of copper (Cu) and zinc oxide (ZnO) coated on a portion of the porous ceramic; And, A CO removal platinum (Pt) catalyst coated on the remaining portion of the porous ceramic; Micro fuel cell, characterized in that consisting of The method according to claim 9 or 10, The micro fuel cell, characterized in that alumina (Al ₂ O ₃ ) is further mixed in the mixed catalyst or platinum catalyst of the copper and zinc oxide. Preparing first and second substrates provided in a MEMS process and having through holes formed therein; Providing an AAO film in which nanopores of CO removal-hydrogen selective transmission means are formed on a substrate side to which fuel (hydrogen) is supplied in the first and second substrates; Forming an electrode on the substrate; Forming catalyst means in the through-holes of the substrate; Finally forming platinum and palladium on the surface of the inner nano pores of the AAO membrane or palladium on the pore surface and platinum on the surface of the AAO membrane to finally provide a CO removal-hydrogen permeation means; And, High temperature bonding the first and second substrates through a polymer electrolyte membrane; Micro fuel cell manufacturing method comprising a. The method of claim 12, Through-holes of the first and second substrates are integrally formed through the substrates through photolithography and wet and dry etching, and evenly distribute air and fuel supplied to the first and second substrates, respectively. Substrate cut portion is a wet etching process, wherein the manufacturing method of the ultra-small fuel cell, characterized in that further formed. The method of claim 12, In the AAO film providing step, aluminum pores are deposited on the incision side of the fuel-supplied second substrate and electropolished, and nanopores are formed through the primary anodization, etching, and the secondary anodization. A method of manufacturing a micro fuel cell, comprising forming an AAO film to be formed. The method according to any one of claims 12 to 14, A cutout is first formed on a second substrate to which fuel is supplied, a through hole is formed in which the catalyst means is formed on the side opposite to the cutout of the substrate, and the AAO film is formed inside the cutout. A method of manufacturing a micro fuel cell, characterized in that the portion and the through hole are sequentially formed. The method of claim 12, The catalyst means formed in the through-holes of the substrate is provided as a porous catalyst coated with platinum on the surface of the internal pores of platinum or porous carbon, and the polymer electrolyte membrane uses Nafion. A method of manufacturing a micro fuel cell which is used. 13. The method of claim 12, wherein in the final provision of the CO removal-hydrogen selective transmission means platinum and palladium are sequentially deposited on the surface of the internal nanopores of the AAO film via electroplating or atomic layer deposition. Or formed on the surface of the AAO membrane and the surfaces of the internal pores of the AAO membrane, respectively.

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