CN216311833U

CN216311833U - Ethanol fuel cell

Info

Publication number: CN216311833U
Application number: CN202120887658.4U
Authority: CN
Inventors: 黄燕; 费金波; 王稼奇
Original assignee: Shenzhen Graduate School Harbin Institute of Technology
Current assignee: Shenzhen Graduate School Harbin Institute of Technology
Priority date: 2021-04-27
Filing date: 2021-04-27
Publication date: 2022-04-15
Anticipated expiration: 2031-04-27

Abstract

The utility model relates to a fuel cell, which comprises an anode, a cathode and an electrolyte sandwiched between the anode and the cathode, wherein the anode comprises a first collector and a PtPdAg/C ternary alloy bifunctional catalyst coated on the first collector, the cathode comprises a second collector and an N, S co-doped carbon catalyst coated on the second collector, and the electrolyte comprises PANAZ hydrogel.

Description

Ethanol fuel cell

Technical Field

The utility model relates to the technical field of batteries, in particular to a fuel battery.

Background

Reliable, low-cost, environmentally friendly energy storage systems (supercapacitors, batteries, etc.) and conversion systems (fuel cells, solar cells, etc.) have become a hotspot in recent decades, with fuel cells being particularly promising due to their high energy density. The fuel cell is a device for directly converting chemical energy of fuel into usable electricity and heat through electrochemical reaction, has a working mode similar to that of a battery, does not need to be charged and exhausted, has the characteristics of high energy conversion efficiency, independence of system efficiency and load, small pollution, simplicity and convenience in operation, manpower saving and the like, and can bear the important responsibility of energy innovation and breakthrough in the 21 st century. The commonly used liquid fuels, such as methanol, ethanol, urea and the like, are convenient to transport, wide in source and low in cost. Despite the various efforts in recent years to produce lightweight, small fuel cells, there are several serious problems: fuel storage difficulties, fuel crossover, etc., which are remote from practical applications.

Among all types of fuel cells, the direct ethanol fuel cell (DAFC) is considered as one of the best candidates for flexible and wearable electronic devices, in addition to the above advantages, in terms of its non-toxicity, human friendliness, variety of green power generation modes, and the like, and thus it is of great strategic importance to develop direct ethanol fuel cell technology for large-scale energy conversion applications. In the DAFC in the past, Pt is a commonly used anode catalyst, but it has low electrocatalytic activity for alcohols and small organic molecules as fuel, and is also easily poisoned by oxidized intermediates, and the cost of Pt is high. Therefore, the development of high-performance and low-cost electrocatalysts is a problem that must be solved.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present invention aims to provide a fuel cell that can solve the above problems.

To this end, the present invention provides a fuel cell comprising an anode, a cathode, and an electrolyte sandwiched between the anode and the cathode, the anode comprising a first current collector and a PtPdAg/C ternary alloy bifunctional catalyst coated on the first current collector, the cathode comprising a second current collector and an N, S co-doped carbon catalyst coated on the second current collector, the electrolyte comprising a PANaZn hydrogel.

In some embodiments, the PtPdAg/C ternary alloy bifunctional catalyst comprises carbon black powder and palladium, platinum and silver ternary alloy particles uniformly dispersed on the surface of the carbon black powder.

In some embodiments, the carbon black powder has a particle size of 20nm to 200 μm.

In some embodiments, the carbon black powder has a particle size of 20nm to 100 μm.

In some embodiments, the particle size of the palladium is 0.1-50 nm, the particle size of the platinum is 0.1-50 nm, and the particle size of the silver is 0.1-50 nm.

In some embodiments, the first current collector and/or the second current collector is a carbon cloth.

In some embodiments, the electrolyte comprises a strong alkaline solution and the PANaZn hydrogel soaked in the strong alkaline solution.

In some embodiments, the fuel cell is an ethanol fuel cell.

The PtPdAg/C ternary alloy catalyst in the fuel cell has excellent capacity of catalyzing ethanol oxidation and acetaldehyde reduction, has good long-term stability, runs well in the fuel cell, contributes to higher open-circuit voltage of the fuel cell, and has wide application prospect.

Drawings

FIG. 1a is a schematic diagram of the preparation of PtPdAg/C catalyst according to example 1 of the utility model.

FIG. 1b is a schematic diagram of the preparation of an electrolyte according to example 1 of the present invention.

Fig. 1c is a schematic view of the preparation of a fuel cell of example 1 of the present invention.

Fig. 2a and 2b are transmission electron microscope images of the PtPdAg/C catalyst prepared in example 1, and fig. 2C and 2d are energy spectra of the PtPdAg/C catalyst prepared in example 1.

FIG. 3a is the cyclic voltammogram of the PtPdAg/C catalyst prepared in example 1 in a 1M KOH solution of saturated nitrogen gas, FIG. 3b is the cyclic voltammogram of the PtPdAg/C catalyst prepared in example 1 and the Pt/C catalyst prepared in comparative example 1 in a 1M KOH solution of saturated nitrogen gas +1M ethanol (ethanol), FIG. 3C is the cyclic voltammogram of the PtPdAg/C catalyst prepared in example 1 and the Pt/C catalyst prepared in comparative example 1 in a 1M KOH solution of saturated nitrogen gas +1M acetaldehyde (acetaldehyde), and FIG. 3d is the cyclic voltammogram of the PtPdAg/C catalyst prepared in example 1 in a 1M KOH solution of saturated nitrogen gas +1M acetaldehyde (acetaldehyde)The PtPdAg/C catalyst and the Pt/C catalyst prepared in comparative example 1 were tested in the presence of ethanol and alkaline electrolyte solution (1M KOH solution) by amperometry, and FIGS. 3e and 3f are I/I plots of the PtPdAg/C catalyst prepared in example 1 and some conventional catalysts_fAnd comparing the values.

Fig. 4a is an OCV curve of the fuel cell manufactured in example 1, fig. 4b is a polarization curve of the fuel cell manufactured in example 1, fig. 4c is a discharge curve of the fuel cell of example 1 at different current densities, fig. 4d is a comparison result of energy densities of the fuel cell of example 1 and various conventional fuel cells, figure 4e shows the rate performance of the fuel cell made in this example 1 at different current densities, figure 4f shows that two straight fuel cells of this example 1 in series can be used to power an electronic clock well, figure 4g shows the discharge voltage of the fuel cell made in accordance with example 1 bent continuously from 0 to 180, fig. 4h shows the discharge voltage of the fuel cell made according to example 1 at different bending times, and fig. 4i shows that the fuel cell made according to example 1 with two bends connected in series can supply power to the electronic clock well.

Detailed Description

The utility model will be described in detail with reference to the accompanying drawings and specific embodiments, so that the technical scheme and the beneficial effects of the utility model are more clear. It is to be understood that the drawings are provided for purposes of illustration and description only and are not intended as a definition of the limits of the utility model, but are drawn to scale.

Example 1

Preparation of a bifunctional catalyst

Referring to fig. 1a, in this embodiment, a liquid phase reduction method is used to synthesize a PtPdAg/C ternary alloy bifunctional catalyst. Specifically, 100mg of cabot carbon black (XC-72R, purchased from Alfa Aesar reagent) and 1-20% acid solution are mixed and fully stirred at 80 ℃ for reaction for 1-5 h (2 h in the embodiment), wherein the acid solution is at least one selected from the following group: nitric acid, hydrochloric acid, sulfuric acid and acetic acid, 60ml of 5% hydrochloric acid is selected for the implementation; in other embodiments, other acid solutions can be selected, for example, a mixed solution of nitric acid and sulfuric acid, wherein the volume ratio of nitric acid to sulfuric acid is 1: 5-5: 1; then repeatedly washing and filtering with deionized water, and drying for 6h at 60 ℃ to obtain carbon black powder. The carbon black powder is a loading substrate of the catalyst, has the characteristic of large active surface area, and the aperture of the carbon black powder is preferably within the range of 20 nm-200 μm, more preferably 20 nm-100 μm, and the aperture of the carbon black powder is about 10 μm in the embodiment. The addition of the carbon black powder can increase the long-term stability of the catalyst. Adding 1-50 mg of carbon black powder into 10-100 ml of dispersion liquid, and performing ultrasonic treatment to completely disperse the carbon black powder. In this example, 4mg of carbon black powder was added to the dispersion, and the mixture was subjected to ultrasonic treatment to obtain a carbon matrix. Wherein the dispersion may be selected from at least one of the following group: ethanol, ethylene glycol, glycerol, acetone, and citric acid solution. In this example, the dispersion was 50ml of an ethanol solution.

Adding 0.1-20 ml of 0.01-10 mol/L (preferably 0.02-9 mol/L) platinum-containing aqueous solution, 0.1-20 ml of 0.01-10 mol/L (preferably 0.02-9 mol/L) palladium-containing aqueous solution, 0.1-20 ml of 0.01-10 mol/L (preferably 0.02-9.5 mol/L) silver-containing aqueous solution and 0.1-20 ml of 0.01-15 mol/L sodium citrate trihydrate solution into the carbon matrix, and reacting at 20-80 ℃ for 0.5-24 h to obtain a mixed solution. In this example, 1.5ml of 1mol/L chloroplatinic acid aqueous solution, 1ml of 1.5mol/L chloroplatinic acid aqueous solution, 1.7ml of 1.3mol/L silver nitrate aqueous solution, and 5ml of 0.8mol/L sodium citrate trihydrate solution were taken and added to the above carbon substrate, stirred uniformly, and reacted at 80 ℃ for 0.5 hour to obtain a mixed solution. It is understood that in other embodiments, other platinum-containing, palladium-containing, and silver-containing aqueous solutions may be selected and the concentrations of each solution may be adapted.

And finally, adding a solution of 1-90 mg of reducing agent dissolved in 1-200 ml of water into the mixed solution, reacting for 0.5-30 h, and centrifugally drying to obtain the bifunctional catalyst, wherein the reducing agent can be selected from at least one of the following groups: bromine water, potassium permanganate, nitric acid, and sodium borohydride. In this example, 10mg of sodium borohydride (NaBH)₄) Dissolving in 20ml of water, slowly dripping into the mixed solution, fully reacting for 2h, centrifuging, and drying at 60 ℃ for 6h to obtain the PtPdAg/C ternary alloy bifunctional catalyst. The particle size of palladium atoms of the prepared PtPdAg/C ternary alloy bifunctional catalyst is preferably 0.1-50 nm, the particle size of platinum atoms is preferably 0.1-50 nm, and the particle size of silver atoms is preferably 0.1-50 nm.

Preparation of electrolyte

And (3) adopting an initiator to carry out polymerization reaction on sodium acrylate and zinc acrylate, and soaking a hydrogel product obtained by the polymerization reaction in a strong alkali solution to obtain the electrolyte.

Referring to fig. 1b, specifically, in this example, first, 44g of Acrylic Acid (AA) was dissolved in 54g of deionized water in an ice bath and sufficiently stirred to obtain an acrylic acid solution. Meanwhile, 26.584g of sodium hydroxide was completely dissolved in 25g of deionized water to obtain a sodium hydroxide solution. The sodium hydroxide solution was slowly added dropwise to the acrylic acid solution, followed by 0.1185g of zinc oxide, which was kept in an ice bath for the entire duration with continuous stirring. Finally, 0.78g Ammonium Persulfate (APS) was added to the oven at 40. + -. 3 ℃ to initiate the free radical polymerization and proceed stably for 30 hours. Thus, a PANaZn hydrogel was obtained. Then, the PANaZn hydrogel was dried in an oven at 110 ℃ for 65 minutes, and then soaked in a 6M KOH +5M ethanol solution to obtain an electrolyte.

Preparation of Fuel cell

Referring to FIG. 1C, 5mg of PtPdAg/C catalyst was added to 1mL of isopropanol and 15. mu.L of 5 wt% Nafion solution to obtain PtPdAg/C catalyst ink, and 10mg of CNS catalyst (N, S co-doped carbon catalyst) was added to a solution containing 0.1mL of 5 wt% Nafion solution, 0.72mL of deionized water, and 0.18mL of isopropanol to obtain CNS catalyst ink. Then, the PtPdAg/C catalyst ink and the CNS catalyst ink were dropped onto a collector, for example, a 1cm × 5cm air-permeable carbon cloth, respectively, to obtain an anode and a cathode, in this example, every 1m²Coated with 0.5mg CNS and 1mg PtPdAg/C catalyst. The electrolyte prepared using the panaq gel described above was then sandwiched between the cathode and anode under air conditions to obtain a carbon cloth (CNS catalyzed)Agent) -PANaZn-carbon cloth (PtPdAg/C catalyst) three-layer structure ethanol (ethanol) fuel cell. The battery is rechargeable and flexible.

The CNS catalyst can be prepared by the following steps: mixing silicon dioxide powder, cane sugar and trithiocyanuric acid, preheating to obtain mixed powder, adding teflon to mix with the mixed powder, and heating the mixture of the mixed powder and the teflon to obtain the N and S co-doped carbon catalyst. In this embodiment, the silica powder, sucrose and trithiocyanuric acid are equal in mass, and the silica powder is preferably fumed silica (fumed silica) having a particle size of 200 nm. In this embodiment, firstly, silicon dioxide powder, sucrose and trithiocyanuric acid are dispersed into deionized water, then concentrated sulfuric acid is added and fully stirred, wherein the weight of the concentrated sulfuric acid accounts for 3% of the sum of the weight of the silicon dioxide powder, the weight of the sucrose and the weight of the trithiocyanuric acid, the mass fraction of the concentrated sulfuric acid is preferably 96% to 97%, and then ultrasonic treatment is performed for about 10min to obtain a mixed solution. And preheating the mixed solution to obtain the mixed powder, wherein in the embodiment, the preheating step comprises two steps: firstly, heating the mixed solution to 100 ℃ to evaporate liquid until the mixed solution becomes solid, and then heating the solid to 160 ℃ to polymerize the sucrose and crosslink the trithiocyanuric acid to obtain mixed powder. In this embodiment, the prepared mixed powder is first milled, then uniformly mixed with an excessive amount of teflon, and after mixing, the mixed powder is heated to 600 ℃ for 1 hour in an inert atmosphere environment, and then heated to 1100 ℃ at a heating rate of 5 ℃/min for 3 hours for pyrolysis to obtain N, S co-doped carbon catalyst powder. Preferably, the teflon is powder with a particle size of 5um, and the ratio of the weight of the teflon to the weight of the fumed silica powder is greater than or equal to 10.

Fig. 2a and 2b are transmission electron microscope morphology diagrams of the PtPdAg/C catalyst prepared in this example 1, and fig. 2C and 2d are energy spectrum diagrams of the PtPdAg/C catalyst prepared in this example 1, and it can be seen from the diagrams that the metal particles Pt, Pd, and Ag are uniformly dispersed on the surface of the carbon matrix and have less agglomeration, which is beneficial to increase the exposed surface area of the metal particles and effectively enhance the catalytic activity of the metal particles.

Example 2

This example is essentially the same as example 1 except that the conditions for preparing the bifunctional catalyst are different.

Specifically, adding carbon black powder into 70ml of glycerol solution, and uniformly mixing; and 10mg of 60% nitric acid is dissolved in 50ml of water and is dropped into the mixed solution for reduction to obtain the PtPdAg/C ternary alloy dual-function catalyst.

Electrochemical performance test results show that the particle size of the metal particles of the PtPdAg/C catalyst prepared in example 2 is 0.1-60 nm, the catalytic ethanol oxidation and acetaldehyde reduction performance is excellent, a CV curve shows higher current density, an ethanol fuel cell assembled by taking the PtPdAg/C as an anode catalyst has an initial open-circuit voltage of about 0.87V, a stable open-circuit voltage of about 0.58V and excellent discharge performance.

Example 3

Specifically, 3ml of a 1mol/L chloropalladate solution was added to this example instead of 1ml of a 1.5mol/L chloropalladate solution.

Electrochemical performance test results show that the particle size of the metal particles of the PtPdAg/C catalyst prepared in example 3 is 0.1-50 nm, the catalytic ethanol oxidation and acetaldehyde reduction performance is excellent, a CV curve shows higher current density, an ethanol fuel cell assembled by taking the PtPdAg/C as an anode catalyst has an initial open-circuit voltage of about 0.85V, a stable open-circuit voltage of about 0.62V and excellent discharge performance.

Example 4

Specifically, the PtPdAg/C ternary alloy bifunctional catalyst is synthesized by adopting a liquid phase reduction method. Specifically, 100mg of cabot black and 10ml of 20% nitric acid are mixed at 80 ℃, fully stirred and reacted for 2 hours, then repeatedly washed by deionized water and filtered, and dried at 80 ℃ overnight to obtain carbon black powder. The carbon black powder has the characteristic of large active surface area, and the aperture of the carbon black powder is about 10 mu m. Adding 16mg of carbon black powder into 20ml of glycol solution, and carrying out ultrasonic treatment for 20min to obtain a carbon matrix.

778 μ L of 0.01mol/L chloroplatinic acid aqueous solution, 2.334ml of 0.01mol/L chloroplatinic acid aqueous solution, 3.89ml of 0.01mol/L silver nitrate aqueous solution and 2ml of 0.1mol/L sodium citrate trihydrate solution were taken and added to the above carbon substrate in this order, stirred uniformly and reacted at 80 ℃ for 0.5 hour to obtain a mixed solution.

And finally, dissolving 15mg of bromine water in 20ml of water, slowly dripping the bromine water into the mixed solution, fully reacting for 2 hours, filtering, washing with ethanol, and drying at 80 ℃ overnight to obtain the PtPdAg/C ternary alloy bifunctional catalyst.

Comparative example 1

In the comparative example, a Pt/C catalyst is synthesized by adopting a liquid phase reduction method, 100mg of carbon black is mixed with 60ml of hydrochloric acid, the mixture is fully stirred and reacts for 2 hours, and then the mixture is filtered and dried for 6 hours at the temperature of 60 ℃ to obtain carbon black powder. The carbon black powder has the characteristic of large active surface area, and the aperture of the carbon black powder is about 10 mu m. Adding 4mg of carbon black powder into 50ml of ethanol solution, and uniformly performing ultrasonic treatment to obtain a carbon matrix. 1ml of 1.5mol/L chloroplatinic acid solution and 5ml of 0.8mol/L sodium citrate solution are added into the carbon matrix and stirred uniformly to obtain a mixed solution. And finally, dissolving 10mg of bromine water in 20ml of water, slowly dripping the bromine water into the mixed solution, fully reacting for 2 hours, centrifuging, and drying at 60 ℃ for 6 hours to obtain the Pt/C catalyst.

The Pt/C catalyst is used for testing the electrochemical performances of ethanol oxidation and acetaldehyde reduction, and the obtained result is far inferior to the PtPdAg/C catalyst in performances.

Specifically, fig. 3a is a cyclic voltammogram of the PtPdAg/C catalyst prepared in example 1 in a 1M KOH solution of saturated nitrogen, fig. 3b is a cyclic voltammogram of the PtPdAg/C catalyst prepared in example 1 and the Pt/C catalyst prepared in comparative example 1 in a 1M KOH solution of saturated nitrogen +1M ethanol (ethanol), and fig. 3C is a cyclic voltammogram of the PtPdAg/C catalyst prepared in example 1 and the Pt/C catalyst prepared in comparative example 1 in a 1M KOH solution of saturated nitrogen +1M acetaldehyde (acetaldehyde), which shows better cyclic performance and current density of the PtPdAg/C catalyst prepared in example 1At a higher level. FIG. 3d is a chronoamperometric test chart of the long-term stability of the PtPdAg/C catalyst prepared in example 1 and the Pt/C catalyst prepared in comparative example 1 in ethanol and alkaline electrolyte solution (1M KOH solution), and it can be seen that the PtPdAg/C catalyst prepared in example 1 shows excellent long-term stability. FIGS. 3e and 3f show I of the PtPdAg/C catalyst prepared in this example 1 and I of some conventional catalysts_fAs a result of comparison of the values, it can be seen that the PtPdAg/C catalyst prepared in this example 1 exhibits extremely high I_f(3238mA mg_{Catalyst and process for preparing same} ^-1). These high catalytic properties are attributed to the increased surface area exposed by the metal nanoparticles and the charge transferred from Pt to Pd, which helps to prevent toxic intermediates from adsorbing on the surface of the ternary alloy during the reaction.

Fig. 4a shows the OCV curve of the fuel cell of example 1, and it can be seen that the initial open circuit voltage of the fuel cell of example 1 is about 0.9V, the stable open circuit voltage is about 0.6V, and the discharge performance is excellent. FIG. 4b is a polarization curve of the fuel cell fabricated in this example 1, based on which the maximum output power density of the fuel cell fabricated in this example 1 was calculated to be 1.7mW cm^-2. FIG. 4c is a graph showing the discharge curves at different current densities of the fuel cell made in example 1, which can be seen at 0.25mA cm^-2The discharge time can be as long as about 23.6h when discharged at the current density of (1), which proves that our fuel cell has good discharge capacity. FIG. 4d shows the result of comparing the energy density of the fuel cell manufactured in example 1 with that of the existing fuel cells, and it can be seen that the fuel cell manufactured in example 1 provides 2.9mWh cm^-2The maximum area energy density that is not available for other fuel cells. Fig. 4e shows the rate performance of the fuel cell made in example 1 at different current densities, and it can be seen that the fuel cell made in example 1 can maintain a high and stable discharge voltage when the current density is multiplied. Fig. 4f shows that two straight fuel cells of this embodiment 1 connected in series can be used to supply power to an electronic clock. FIG. 4g shows the discharge voltage of the fuel cell of example 1, which is continuously bent from 0 to 180, indicating that the maximum distance of the fuel cell of example 1 can be obtainedWhen the fuel cell is bent to 180 degrees, and sequentially bent to 30 degrees, 60 degrees, 180 degrees and finally bent to 0 degree, the fuel cell manufactured by the embodiment 1 still maintains stable discharge voltage. Fig. 4h shows the discharge voltage of the fuel cell made in this example 1 at different bending times, and in the experiment, the fuel cell made in this example 1 is bent 100 times every 180s, the bending angle is 30 °, and the total bending time is 1000 times, and it can be seen from the figure that the fuel cell made in this example 1 still maintains the high and stable discharge voltage during the whole bending process. Fig. 4i shows that two bent fuel cells of this embodiment 1 in series can provide good power for an electronic clock. All these results strongly demonstrate that our fuel cell exhibits excellent and stable performance in both straight and curved conditions, which is very promising in future applications.

The fuel cell of the embodiments of the present invention performs an Ethanol Oxidation Reaction (EOR) and an Acetaldehyde Reduction Reaction (ARR) using a bifunctional catalyst (capable of oxidizing ethanol to acetaldehyde as well as an acetaldehyde rim) and uses a bifunctional hydrogel as a fuel reservoir and an Anion Exchange Membrane (AEM). The PtPdAg/C ternary alloy with the bifunctional catalytic performance shows extremely high I in EOR_f(3238mA mg_{Catalyst and process for preparing same} ^-1) The overpotential in the ARR test is significantly lower than that of the Pt/C catalyst. In addition, the sodium polyacrylate and zinc Polyacrylate (PANAZ) hydrogel has excellent ethanol storage capacity, and can store 66.5g of ethanol at most_Ethanol/g_PANaZn10.723g of storable acetaldehyde_Acetaldehyde/g_PANaZn. Benefiting from Zn²⁺The introduction of (1) can allow ethanol and acetaldehyde molecules to enter a cross-linked structure. Furthermore, due to the introduction of KOH, the hydrogel has a high ionic conductivity of about 0.16S/cm, ensuring its use as a good AEM. As a result, the fuel cell showed a high rechargeable performance over 100 cycles (1000 minutes). The fuel cell of the present embodiment can maintain the voltage well, and can supply power to the electronic clock easily, and can be bent arbitrarily in the range of 0 ° to 180 °, with excellent flexibility. In addition, it has high performance (discharge time as long as 23.6 hours, outstanding rate performance), easy assembly and partsLess cost. The high performance, truly rechargeable and flexible ethanol fuel cell opens up a new generation of functional fuel cells for flexible electronic products.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-listed embodiments, and any simple changes or equivalent substitutions of technical solutions that can be obviously obtained by those skilled in the art within the technical scope of the present invention are within the protection scope of the present invention.

Claims

1. An ethanol fuel cell, the fuel cell comprises an anode, a cathode and an electrolyte sandwiched between the anode and the cathode, the fuel cell is characterized in that the anode comprises a first collector and a PtPdAg/C ternary alloy bifunctional catalyst coated on the first collector, the cathode comprises a second collector and an N, S co-doped carbon catalyst coated on the second collector, and the electrolyte is PANaZn hydrogel.

2. The ethanol fuel cell of claim 1, wherein the particle size of the palladium in the PtPdAg/C ternary alloy bifunctional catalyst is 0.1 to 50nm, the particle size of the platinum is 0.1 to 50nm, and the particle size of the silver is 0.1 to 50 nm.

3. The ethanol fuel cell of claim 1, wherein the first and/or second current collectors are carbon cloths.