An electrode material for a fuel cell and a preparation method thereof

Abstract

The present invention belongs to the field of fuel cells, and particularly relates to an electrode material for fuel cells and a preparation method thereof, comprising the following steps: preparing a polyimide containing amino POSS; performing primary pyrolysis, and sequentially etching, cleaning, and drying the product to obtain primary carbonized polyimide; grinding the primary carbonized polyimide and then performing pyrolysis again, and sequentially etching, cleaning, and drying the product to obtain the electrode material for fuel cells. The electrode material has a good graphite structure and a rich pore structure, which can ensure good electrical conductivity of the material while enabling ions and electrons to transfer rapidly within the pores; at the same time, the introduction of non-metallic nitrogen heteroatoms can increase active sites and significantly improve the electrochemical activity of the material, making it suitable as an electrode material for fuel cells.

Description

Technical Field

[0001] The present invention belongs to the field of fuel cells, and particularly relates to an electrode material for a fuel cell and a preparation method thereof. Background Art

[0002] The increase in global energy consumption, mainly from limited fossil fuel resources, may lead to depletion of reserves and an increase in environmental problems, which may ultimately lead to serious health problems. Therefore, there is an urgent need to explore and develop pollution-free, renewable, and sustainable energy sources. Nature produces a large amount of biomass waste every day (including agricultural waste, by-products and residues, lignocellulosic biomass, woody biomass). Biomass currently accounts for 15% of global energy consumption because it is easily convertible into gaseous, liquid, and solid-phase materials. However, a large amount of biomass dumped or burned in the open air will lead to the release of harmful pollutants. The emergence of fuel cells and other electrochemical devices has paved the way for a series of applications of biomass in clean energy.

[0003] Fuel cells have the same composition as ordinary batteries. A single cell consists of a positive electrode, a negative electrode, and an electrolyte membrane and electrolyte solution. The difference is that the active materials of ordinary batteries are stored inside the battery, and the limited internal space restricts the storage amount of active materials, thereby restricting the capacity of ordinary batteries. However, neither of the two electrodes of a fuel cell contains active materials, and the electrodes are only catalytic elements. Therefore, a fuel cell can be regarded as an efficient energy conversion machine that can effectively utilize electrochemical energy. When the battery is working, fuel and oxygen are continuously supplied from the outside for reaction. When the fuel input is not interrupted and the reaction is continuous, the fuel cell can continue to generate electricity.

[0004] The polarization loss caused by the oxygen reduction reaction (ORR) in fuel cells and metal-air batteries has become one of the key factors seriously affecting the overall performance of these energy storage and conversion devices. So far, platinum and its alloys are considered to be the best electrocatalysts for accelerating the ORR process. In addition to the high cost, they also have the disadvantages of poor stability and susceptibility to cross effects, which are becoming the main obstacles to the commercialization of these electrochemical power devices. Generally speaking, in order to reduce costs and encourage wide use, researchers are mainly committed to replacing expensive platinum-based catalysts with ORR catalysts with lower costs. In search of platinum-free catalysts, promising alternatives have been found, including non-noble metal catalysts, nanostructured transition metal oxides, and nitrogen-doped carbon materials, etc.

[0005] Among the various types of catalysts mentioned above, whether they are non-precious metal catalysts or nanostructured transition metal catalysts, they are prone to react with acids in an acidic environment to produce metal salts, thereby reducing the catalytic activity of the catalyst. In an alkaline environment, metals react with alkalis to produce metal hydroxides, resulting in the loss of metals and affecting the reaction rate. If these two types of metal catalysts are used extensively, it will cause a large loss of metal resources, polluting the environment on the one hand and increasing costs on the other hand. Therefore, people have been vigorously promoting various advanced metal-free ORR catalysts to replace platinum-based materials.

[0006] In summary, if the electrocatalyst for oxygen reduction reaction cannot achieve high activity, high stability, and low cost, the platinum-based catalyst cannot be replaced, and then the large-scale practical application of fuel cells will be difficult to achieve. Here, the nitrogen-doped carbon structure can be used as a metal-free catalyst, which has advantages such as catalytic activity, long-term operation stability, and tolerance to cross effects, and is much better than platinum for oxygen reduction in alkaline fuel cells. Nitrogen-doped porous carbon materials have been proven to be one of the most promising high-efficiency ORR catalysts because they can regulate the charge redistribution of carbon atoms, enhance the electron transport ability, and introduce edge defects, which is beneficial to electron transfer. Nitrogen-doped carbon structure materials have also become the most promising materials for cathode and anode electrode materials in future fuel cells. However, the nitrogen-doped carbon structure materials prepared by existing technologies have a low specific surface area and low catalytic efficiency, which limits their application. Summary of the Invention

[0007] The purpose of the present invention is to provide an electrode material for fuel cells and its preparation method. The carbon material prepared by modifying polyimide with amino-POSS endows the carbon material with a high specific surface area and a porous structure to solve the problems mentioned in the above background technology.

[0008] To achieve the above purpose, the present invention provides the following technical solution: A preparation method of an electrode material for fuel cells, including the following steps:

[0009] (1) Add dianhydride monomers and diamine monomers to an organic solvent. After stirring and reacting for a period of time, add amino-POSS and continue to react to generate a polyamic acid solution; the mass of amino-POSS is 0.1-5 wt% of the sum of the masses of dianhydride monomers and diamine monomers.

[0010] Specifically, the stirring reaction time is 2 - 4 h, and the continuous reaction time is 5 - 8 h. Further, the process steps are as follows: The diamine monomer is added to an organic solvent, and under continuous stirring conditions, the dianhydride monomer is added to the organic solvent in 3 - 5 portions at intervals of 3 - 8 minutes each. After the addition of the dianhydride monomer is completed, stirring reaction is carried out for 2 - 4 h, and then amino-POSS is added, and continuous reaction is carried out for 5 - 8 h to form a polyamic acid solution. Reacting the dianhydride monomer and the diamine monomer for a period of time in advance and then adding amino-POSS can not only promote the progress of the polymerization reaction, but also make the amino-POSS uniformly dispersed in the resin matrix.

[0011] Further, the stirring rate is 150 - 250 r / min;

[0012] Further, the dianhydride monomer is selected from one or more of pyromellitic dianhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, diphenyl sulfone-3,4,3',4'-tetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl) sulfide dianhydride, 2,2'-bis(3,4-dicarboxy)hexafluoropropane dianhydride, 2,3,3',4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, m-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, p-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)biphenyl dianhydride, 2,2-bis[(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride.

[0013] Further, the diamine monomer is selected from one or more of p-phenylenediamine, m-phenylenediamine, 3,3'-dimethylbenzidine, 2,2'-dimethylbenzidine, 2,4-diaminotoluene, 2,6-diaminotoluene, 3,5-diaminobenzoic acid, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane (methylenediamine), 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-dicarboxy-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, 4,4'-diaminobenzanilide, 3,3'-dimethoxybenzidine, 2,2'-dimethoxybenzidine, 3,3'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diamino-4,4'-dichlorobenzophenone, 3,3'-diamino-4,4'-dimethoxybenzophenone.

[0014] Benefiting from the excellent thermal stability of polyimide, its morphology is well retained after pyrolysis. By selecting polyimide monomers, the structure control of the target nitrogen-doped carbon materials can be achieved.

[0015] (2) Drop the polyamic acid solution into deionized water to precipitate polyamic acid powder, and obtain polyimide after gradient temperature-rising thermal imidization.

[0016] Polyimide is a low-cost engineering plastic with a rigid aromatic skeleton, which is easy to carbonize and has a high carbon yield. Moreover, the nitrogen-containing five-membered imide heterocyclic groups are evenly distributed in the polyimide skeleton, laying a foundation for the synchronous in-situ doping of nitrogen atoms during the carbonization process. The doping process is easier and the doping effect is more uniform.

[0017] Further, the gradient temperature-rising thermal imidization process is as follows: the heating rate is 2-6 °C / min, heating from room temperature to 70-80 °C and then holding for 0.2-1 h, then heating to 100-110 °C and holding for 1-1.5 h, then heating to 130-150 °C and holding for 1-1.5 h, then heating to 180-200 °C and holding for 1-1.5 h, then heating to 230-250 °C and holding for 1-1.5 h, then heating to 260-270 °C and holding for 1-1.5 h.

[0018] (3) The polyimide is subjected to primary pyrolysis in an inert gas atmosphere. The product is successively etched with acid, washed, and dried to obtain primary carbonized polyimide. The primary pyrolysis temperature is 900 - 1200 °C, and the time is 0.5 - 2 h.

[0019] (4) After grinding the primary carbonized polyimide, it is pyrolyzed again in an inert gas atmosphere. The product is successively etched with acid, washed, and dried to obtain the electrode material for fuel cells. The secondary pyrolysis temperature is 500 - 800 °C, and the time is 2 - 5 h. The acid etching is carried out in two steps. Compared with the common one-step acid etching process in the art, the first acid etching can promote the exposure of internal silicon oxides, which is not only beneficial to the secondary acid etching but also promotes the low-temperature carbonization process. After grinding the primary carbonized polyimide, it can also promote the exposure of internal silicon oxides and improve the efficiency of the carbonization process.

[0020] Platinum, as the most common electrode material, has the disadvantages of high price, low abundance, and poor tolerance to impurities. To solve these bottleneck problems of precious metals, the present invention prepares a metal-free heteroatom-doped carbon-based material. The metal-free heteroatom-doped carbon material has become the most promising electrode material due to its low price, controllable pore structure, and high tolerance to impurities. Compared with the conventional hydrothermal carbonization method and template method, the pyrolysis method for preparing nitrogen-doped carbon materials has a simpler process and is suitable for industrial promotion. By adjusting the carbonization temperature, the nitrogen doping content and type in the nitrogen-doped carbon material can be regulated, thereby optimizing its characteristics as an electrode material.

[0021] Further, in step (1), the organic solvent is one or more of N,N-dimethylacetamide, dimethyl sulfoxide, N,N-dimethylformamide, and N-methylpyrrolidone.

[0022] Further, in step (1), the amino-containing POSS is one or more of octaaminophenyl silsesquioxane, octaaminopropyl silsesquioxane, aminopropylisobutyl silsesquioxane, and aminopropylisooctyl silsesquioxane.

[0023] Amino-containing POSS has two aspects of functions in the carbon matrix. On the one hand, the amino group in POSS plays a role in nitrogen doping. As a non-metal element incorporated into carbon nanomaterials, its size and electronegativity are different from those of carbon atoms, which will lead to changes in electron modulation, charge distribution and electronic properties, greatly changing the chemical properties of carbon nanomaterials, thereby improving the performance of carbon nanomaterials. On the other hand, the unique hollow closed cage structure of POSS undergoes volume shrinkage during the calcination process, introducing a porous structure. In addition, the SiOC (such as SiO2) structure formed by the transformation of POSS therein will be corroded by hydrofluoric acid during the cleaning process, further improving the porous structure of carbon. It should be noted that the amount of POSS needs to be controlled. When the mass of amino-containing POSS exceeds 5wt% of the sum of the monomer masses, it is not only not conducive to the progress of the polymerization reaction, but also affects the overall structure of the polyimide, resulting in a decrease in mechanical strength and the collapse of the internal porous structure during the heating carbonization process, which is not conducive to the formation of conductive paths and affects the performance of carbon materials.

[0024] Further, the molar ratio of the dianhydride monomer to the diamine monomer in step (1) is 1:(1 - 1.05).

[0025] Further, the inert gas in steps (3) and (4) is at least one of argon, nitrogen, and helium.

[0026] Further, the acid etching in steps (3) and (4) is carried out using a hydrofluoric acid solution, and the mass concentration of the hydrofluoric acid solution is 5 - 15wt%.

[0027] Further, the cleaning in steps (3) and (4) is to first wash with deionized water 2 - 4 times, and then wash with absolute ethanol 1 - 3 times.

[0028] Further, the heating rate of primary pyrolysis in step (3) is 5 - 10°C / min. A faster heating rate can promote the rapid formation of the basic structure and prevent the shrinkage and deformation of the pore structure.

[0029] Further, the heating rate of re-pyrolysis in step (4) is 1 - 5°C / min.

[0030] Furthermore, the primary pyrolysis temperature is 950 - 1100 °C and the time is 1.3 - 2 h; the re-pyrolysis temperature is 700 - 800 °C and the time is 2.5 - 4.5 h. Higher pyrolysis temperature and longer pyrolysis time are beneficial to the formation of a large specific surface area and the development of a porous structure of the prepared material. However, excessive pyrolysis may cause the collapse of the pore structure of the material, thereby reducing its specific surface area and its electrical properties. The carbon material is prepared by a two-step pyrolysis method in the present invention. First, polyimide is carbonized at a higher heating rate and a higher temperature. On the one hand, it promotes the rapid carbonization and shaping of polyimide, especially the POSS structure, to prevent the collapse of the structure during the subsequent carbonization process; on the other hand, the higher temperature promotes the pyrolysis of the POSS structure and the formation of the SiOC (such as SiO2) structure. Then, the temperature is reduced from a higher temperature to a lower carbonization temperature to further carbonize the material and promote the formation of a porous structure. The POSS-modified polyimide carbon material prepared by the two-step method has a large specific surface area and a rich pore structure, which is beneficial to the improvement of the electrical conductivity of the carbon material.

[0031] On the other hand, the present invention also provides an electrode material for a fuel cell. The electrode material prepared in the present invention has a relatively high specific surface area, which enables the reactants to fully contact with the active sites; in addition, the electrode material has a good graphite structure and a rich pore structure, which can ensure good electrical conductivity of the material while enabling ions and electrons to transfer rapidly in the pores; at the same time, the introduction of non-metallic nitrogen heteroatoms can increase the active sites and significantly improve the electrochemical activity of the material, and it is suitable for use as an electrode material for a fuel cell, especially a microbial fuel cell.

[0032] Beneficial effects: The preparation of a self-doped carbon material is realized by using polyimide as a precursor material. Polyimide is a low-cost engineering plastic with a rigid aromatic skeleton, which is easy to carbonize, has a high carbon yield, and is easier to dope and has a more uniform doping effect. The amino group in POSS plays a role in nitrogen doping, greatly changing the chemical properties of the carbon nanomaterial, thereby improving the performance of the carbon nanomaterial; at the same time, the unique hollow closed cage structure of POSS undergoes volume shrinkage during the calcination process, introducing a porous structure. The SiOC (such as SiO2) structure formed by the conversion of POSS therein will be corroded by hydrofluoric acid, further improving the porous structure of the carbon. The POSS-modified polyimide carbon material prepared by the two-step method has a large specific surface area and a rich pore structure, which is beneficial to the improvement of the electrical conductivity of the carbon material.

[0033] The electrode material has a high specific surface area, which can allow the reactants to fully contact the active sites. In addition, the electrode material has a good graphite structure and a rich pore structure, which can ensure good conductivity of the material while enabling ions and electrons to transfer rapidly within the pores. At the same time, the introduction of non-metallic nitrogen heteroatoms can increase the active sites and significantly improve the electrochemical activity of the material, making it suitable as an electrode material for fuel cells, especially microbial fuel cells. Detailed implementation mode

[0034] To better understand the technical content of the present invention, specific embodiments are provided below to further illustrate the present invention.

[0035] Unless otherwise specified, the experimental methods used in the embodiments of the present invention are all conventional methods.

[0036] Unless otherwise specified, the materials, reagents, etc. used in the embodiments of the present invention can all be obtained from commercial channels.

[0037] Embodiment 1

[0038] A preparation method of an electrode material for a fuel cell includes the following steps:

[0039] (1) Add a diamine monomer to an organic solvent. Under continuous stirring, add a dianhydride monomer to the organic solvent in 3 portions at intervals of 5 minutes. After the addition of the dianhydride monomer is completed, stir and react for 3.2 h, then add amino-POSS and continue to react for 7.5 h to form a polyamic acid solution; the mass of amino-POSS is 2.5 wt% of the sum of the masses of the dianhydride monomer and the diamine monomer; the stirring rate is 200 r / min;

[0040] The dianhydride monomer is selected from pyromellitic dianhydride; the diamine monomer is selected from 4,4'-diaminodiphenyl ether; the amino-POSS is octaaminophenylcage silsesquioxane; the organic solvent is N,N-dimethylacetamide; the molar ratio of the dianhydride monomer to the diamine monomer is 1:1.01;

[0041] (2) Drop the polyamic acid solution into deionized water to precipitate polyamic acid powder, and obtain polyimide after gradient temperature rise thermal imidization;

[0042] The gradient temperature rise thermal imidization process is as follows: the heating rate is 4 °C / min, heat from room temperature to 75 °C and hold for 0.5 h, then heat to 100 °C and hold for 1.4 h, then heat to 130 °C and hold for 1.2 h, then heat to 180 °C and hold for 1.3 h, then heat to 230 °C and hold for 1.3 h, then heat to 260 °C and hold for 1.2 h;

[0043] (3) The polyimide is subjected to primary pyrolysis in an argon atmosphere. After the product is successively etched with acid, washed, and dried, primary carbonized polyimide is obtained. The heating rate of primary pyrolysis is 5 °C / min; the primary pyrolysis temperature is 950 °C, and the time is 2 h. The acid etching is carried out using a hydrofluoric acid solution with a mass concentration of 8 wt%. The washing is first done by washing 3 times with deionized water and then 2 times with absolute ethanol.

[0044] (4) After the primary carbonized polyimide is ground, it is pyrolyzed again in an argon atmosphere. After the product is successively etched with acid, washed, and dried, the electrode material for fuel cells is obtained. The heating rate of the second pyrolysis is 3 °C / min, the second pyrolysis temperature is 700 °C, and the time is 4.5 h. The acid etching is carried out using a hydrofluoric acid solution with a mass concentration of 8 wt%. The washing is first done by washing 3 times with deionized water and then 2 times with absolute ethanol. The specific surface area and pore volume of the product are tested by nitrogen adsorption experiments, and its conductivity is tested by a four-probe tester. The specific surface area is 924 m 2 g -1 , the pore volume is 0.53 cm 3 g -1 ; the conductivity is 12.2 Scm -1 .

[0045] Example 2

[0046] A preparation method of an electrode material for fuel cells, comprising the following steps:

[0047] (1) Add the diamine monomer to an organic solvent. Under continuous stirring, add the dianhydride monomer to the organic solvent in 3 portions at intervals of 5 minutes. After the addition of the dianhydride monomer is completed, stir and react for 4 h, then add amino-POSS, and continue to react for 6 h to form a polyamic acid solution. The mass of amino-POSS is 5 wt% of the sum of the masses of the dianhydride monomer and the diamine monomer; the stirring rate is 200 r / min;

[0048] The dianhydride monomer is selected from 3,3',4,4'-biphenyltetracarboxylic dianhydride; the diamine monomer is selected from 4,4'-diaminodiphenylmethane; the amino-POSS is octaaminophenylcage silsesquioxane; the organic solvent is N,N-dimethylformamide; the molar ratio of the dianhydride monomer to the diamine monomer is 1:1.05;

[0049] (2) Drop the polyamic acid solution into deionized water to precipitate polyamic acid powder, and obtain polyimide after gradient heating and thermal imidization.

[0050] The gradient heating thermal imidization process is as follows: the heating rate is 4 °C / min, heating from room temperature to 75 °C and holding for 0.5 h, then heating to 100 °C and holding for 1.4 h, then heating to 150 °C and holding for 1.2 h, then heating to 200 °C and holding for 1.3 h, then heating to 250 °C and holding for 1.3 h, then heating to 270 °C and holding for 1.2 h;

[0051] (3) Pyrolyze the polyimide under an argon atmosphere for the primary pyrolysis. The product is successively etched with acid, washed, and dried to obtain the primary carbonized polyimide; the heating rate of the primary pyrolysis is 6 °C / min; the primary pyrolysis temperature is 1100 °C and the time is 1.3 h; the acid etching is carried out with a hydrofluoric acid solution with a mass concentration of 8 wt%; the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol;

[0052] (4) After grinding the primary carbonized polyimide, pyrolyze it again under an argon atmosphere. The product is successively etched with acid, washed, and dried to obtain the electrode material for fuel cells; the heating rate of the secondary pyrolysis is 3 °C / min, the secondary pyrolysis temperature is 800 °C, and the time is 2.5 h; the acid etching is carried out with a hydrofluoric acid solution with a mass concentration of 8 wt%; the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol. The specific surface area and pore volume of the product are tested by nitrogen adsorption experiments, and its conductivity is tested by a four-probe tester. The specific surface area is 1024 m 2 g -1 , the pore volume is 0.62 cm 3 g -1 ; the conductivity is 17.1 S / cm -1 .

[0053] Example 3

[0054] A preparation method of an electrode material for fuel cells, comprising the following steps:

[0055] (1) Add the diamine monomer to the organic solvent. Under the condition of continuous stirring, add the dianhydride monomer to the organic solvent in 3 times at intervals of 5 minutes. After the addition of the dianhydride monomer is completed, stir and react for 3.2 h, then add amino-POSS and continue to react for 6 h to form a polyamic acid solution; the mass of amino-POSS is 3 wt% of the sum of the masses of the dianhydride monomer and the diamine monomer; the stirring rate is 200 r / min;

[0056] The dianhydride monomer is selected from a mixture of 3,3',4,4'-diphenylether tetracarboxylic dianhydride and 2,2'-bis(3,4-dicarboxylic acid) hexafluoropropane dianhydride with a molar ratio of 1:1; the diamine monomer is selected from 4,4'-diaminodiphenyl ether; the amino-POSS is octaaminophenyl silsesquioxane; the organic solvent is N,N-dimethylacetamide; the molar ratio of the dianhydride monomer to the diamine monomer is 1:1.03;

[0057] (2) The polyamic acid solution was dropped into deionized water to precipitate polyamic acid powder, and polyimide was obtained after gradient temperature-rising thermal imidization;

[0058] The process of gradient temperature-rising thermal imidization was as follows: the heating rate was 4 °C / min, rising from room temperature to 75 °C and holding for 0.5 h, then rising to 100 °C and holding for 1.4 h, then rising to 135 °C and holding for 1.2 h, then rising to 185 °C and holding for 1.3 h, then rising to 245 °C and holding for 1.3 h, and then rising to 262 °C and holding for 1.2 h;

[0059] (3) The polyimide was subjected to primary pyrolysis in an argon atmosphere, and the product was successively etched with acid, washed, and dried to obtain primary carbonized polyimide; the heating rate of primary pyrolysis was 6 °C / min; the primary pyrolysis temperature was 1050 °C and the time was 1.5 h; the acid etching was carried out with a hydrofluoric acid solution with a mass concentration of 8 wt%, and the washing was first carried out 3 times with deionized water and then 2 times with absolute ethanol;

[0060] (4) After the primary carbonized polyimide was ground, it was pyrolyzed again in an argon atmosphere, and the product was successively etched with acid, washed, and dried to obtain the electrode material for fuel cells; the heating rate of the secondary pyrolysis was 3 °C / min, the secondary pyrolysis temperature was 730 °C, and the time was 3.1 h; the acid etching was carried out with a hydrofluoric acid solution with a mass concentration of 8 wt%, and the washing was first carried out 3 times with deionized water and then 2 times with absolute ethanol. The specific surface area and pore volume of the product were tested by nitrogen adsorption experiment, and its conductivity was tested by a four-probe tester. The specific surface area was 1147 m 2 g -1 , and the pore volume was 0.63 cm 3 g -1 ; the conductivity was 19.2 S cm -1 .

[0061] Example 4

[0062] A preparation method of an electrode material for fuel cells, comprising the following steps:

[0063] (1) The diamine monomer was added to an organic solvent, and under continuous stirring conditions, the dianhydride monomer was added to the organic solvent in 3 portions at intervals of 5 minutes. After the addition of the dianhydride monomer was completed, the reaction was stirred for 3.7 h, and then amino-POSS was added and the reaction continued for 7 h to form a polyamic acid solution; the mass of amino-POSS was 3.2 wt% of the sum of the masses of the dianhydride monomer and the diamine monomer; the stirring rate was 200 r / min;

[0064] The dianhydride monomer is selected from a mixture of 3,3',4,4'-biphenyltetracarboxylic dianhydride and 3,3',4,4'-diphenylether tetracarboxylic dianhydride with a molar ratio of 1:1; the diamine monomer is selected from 4,4'-diaminodiphenylmethane; the amino-containing POSS is octaaminophenylcage silsesquioxane; the organic solvent is N,N-dimethylformamide; the molar ratio of the dianhydride monomer to the diamine monomer is 1:1.04;

[0065] (2)Drop the polyamic acid solution into deionized water to precipitate polyamic acid powder, and obtain polyimide after gradient temperature-rising thermal imidization;

[0066] The process of gradient temperature-rising thermal imidization is as follows: the heating rate is 4°C / min, heat up from room temperature to 75°C and keep warm for 0.5 h, then heat up to 100°C and keep warm for 1.4 h, then heat up to 142°C and keep warm for 1.2 h, then heat up to 193°C and keep warm for 1.3 h, then heat up to 248°C and keep warm for 1.3 h, then heat up to 266°C and keep warm for 1.2 h;

[0067] (3)Carry out primary pyrolysis on the polyimide in an argon atmosphere, and the product is sequentially etched with acid, washed, and dried to obtain primary carbonized polyimide; the heating rate of primary pyrolysis is 6°C / min; the primary pyrolysis temperature is 990°C and the time is 1.7 h; the acid etching is carried out with a hydrofluoric acid solution with a mass concentration of 8 wt%, and the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol;

[0068] (4)After grinding the primary carbonized polyimide, pyrolyze it again in an argon atmosphere, and the product is sequentially etched with acid, washed, and dried to obtain the electrode material for fuel cells; the heating rate of the second pyrolysis is 3°C / min, the second pyrolysis temperature is 770°C, and the time is 4.1 h; the acid etching is carried out with a hydrofluoric acid solution with a mass concentration of 8 wt%, and the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol. The specific surface area and pore volume of the product are tested by nitrogen adsorption experiment, and its conductivity is tested by a four-probe tester. The specific surface area is 1068 m 2 g -1 , the pore volume is 0.57 cm 3 g -1 ; the conductivity is 14.8Scm -1 .

[0069] Example 5

[0070] A preparation method of an electrode material for fuel cells, comprising the following steps:

[0071] (1) Add the diamine monomer into an organic solvent. Under continuous stirring, add the dianhydride monomer into the organic solvent in three portions at intervals of 5 minutes each. After the addition of the dianhydride monomer is completed, stir and react for 3.6 h, then add amino-POSS and continue to react for 6 h to form a polyamic acid solution; the mass of amino-POSS is 3.4 wt% of the sum of the masses of the dianhydride monomer and the diamine monomer; the stirring rate is 200 r / min;

[0072] The dianhydride monomer is selected from a mixture of pyromellitic dianhydride and 3,3',4,4'-biphenyltetracarboxylic dianhydride with a molar ratio of 2:1; the diamine monomer is selected from 4,4'-diaminodiphenyl ether; the amino-POSS is octaaminophenylcage silsesquioxane; the organic solvent is N,N-dimethylformamide; the molar ratio of the dianhydride monomer to the diamine monomer is 1:1.03;

[0073] (2) Drop the polyamic acid solution into deionized water to precipitate polyamic acid powder, and obtain polyimide after gradient heating thermal imidization;

[0074] The process of gradient heating thermal imidization is as follows: the heating rate is 4 °C / min, heat from room temperature to 75 °C and hold for 0.5 h, then heat to 100 °C and hold for 1.4 h, then heat to 140 °C and hold for 1.2 h, then heat to 193 °C and hold for 1.3 h, then heat to 241 °C and hold for 1.3 h, then heat to 267 °C and hold for 1.2 h;

[0075] (3) Carry out primary pyrolysis of the polyimide in an argon atmosphere. The product is successively etched with acid, washed, and dried to obtain primary carbonized polyimide; the heating rate of primary pyrolysis is 3 °C / min; the primary pyrolysis temperature is 1000 °C and the time is 1.7 h; the acid etching is carried out with a hydrofluoric acid solution with a mass concentration of 8 wt%, and the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol;

[0076] (4) Grind the primary carbonized polyimide and then pyrolyze it again in an argon atmosphere. The product is successively etched with acid, washed, and dried to obtain the electrode material for fuel cells; the heating rate of the second pyrolysis is 3 °C / min, the second pyrolysis temperature is 780 °C, and the time is 3.8 h; the acid etching is carried out with a hydrofluoric acid solution with a mass concentration of 8 wt%, and the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol. The specific surface area and pore volume of the product are tested by nitrogen adsorption experiment, and its conductivity is tested by a four-probe tester. The specific surface area is 973 m 2 g -1 , the pore volume is 0.55 cm 3 g -1 ; the conductivity is 18.1 S / cm -1 .

[0077] Example 6

[0078] A preparation method of an electrode material for a fuel cell, comprising the following steps:

[0079] (1) Add a diamine monomer into an organic solvent. Under continuous stirring, add a dianhydride monomer into the organic solvent in 3 portions at intervals of 5 minutes each. After the addition of the dianhydride monomer is completed, directly add amino-POSS and continue the reaction for 9.6 h to form a polyamic acid solution; the mass of amino-POSS is 3.4 wt% of the sum of the masses of the dianhydride monomer and the diamine monomer; the stirring rate is 200 r / min;

[0080] The dianhydride monomer is selected from a mixture of pyromellitic dianhydride and 3,3',4,4'-biphenyltetracarboxylic dianhydride with a molar ratio of 2:1; the diamine monomer is selected from 4,4'-diaminodiphenyl ether; the amino-POSS is octaaminophenylcage silsesquioxane; the organic solvent is N,N-dimethylformamide; the molar ratio of the dianhydride monomer to the diamine monomer is 1:1.03;

[0081] (2) Drop the polyamic acid solution into deionized water to precipitate polyamic acid powder, and obtain polyimide after gradient heating thermal imidization;

[0082] The process of gradient heating thermal imidization is as follows: the heating rate is 4 °C / min, heat from room temperature to 75 °C and keep warm for 0.5 h, then heat to 100 °C and keep warm for 1.4 h, then heat to 140 °C and keep warm for 1.2 h, then heat to 193 °C and keep warm for 1.3 h, then heat to 241 °C and keep warm for 1.3 h, then heat to 267 °C and keep warm for 1.2 h;

[0083] (3) Carry out primary pyrolysis of the polyimide in an argon atmosphere. The product is sequentially etched with acid, washed, and dried to obtain primary carbonized polyimide; the heating rate of primary pyrolysis is 6 °C / min; the primary pyrolysis temperature is 1000 °C and the time is 1.7 h; the acid etching is carried out using a hydrofluoric acid solution with a mass concentration of 8 wt%, and the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol;

[0084] (4) Grind the primary carbonized polyimide, and then pyrolyze it again in an argon atmosphere. The product is sequentially etched with acid, washed, and dried to obtain the electrode material for the fuel cell; the heating rate of the second pyrolysis is 3 °C / min, the second pyrolysis temperature is 780 °C and the time is 3.8 h; the acid etching is carried out using a hydrofluoric acid solution with a mass concentration of 8 wt%, and the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol. The specific surface area and pore volume of the product are tested by nitrogen adsorption experiment, and its conductivity is tested by a four-probe tester. The specific surface area is 1035 m 2 g -1 ², and the pore volume is 0.59 cm 3 ³ / g-1 ; The conductivity is 15.4 S / cm -1 .

[0085] Example 7

[0086] A method for preparing an electrode material for a fuel cell, comprising the following steps:

[0087] (1) Add a diamine monomer to an organic solvent. Under continuous stirring conditions, add a dianhydride monomer to the organic solvent in 3 portions at intervals of 5 minutes each. After the addition of the dianhydride monomer is complete, stir and react for 3.6 h, then add amino-POSS and continue to react for 6 h to form a polyamic acid solution; the mass of amino-POSS is 3.4 wt% of the sum of the masses of the dianhydride monomer and the diamine monomer; the stirring rate is 200 r / min;

[0088] The dianhydride monomer is selected from a mixture of pyromellitic dianhydride and 3,3',4,4'-biphenyltetracarboxylic dianhydride with a molar ratio of 2:1; the diamine monomer is selected from 4,4'-diaminodiphenyl ether; the amino-POSS is octaaminophenylcage silsesquioxane; the organic solvent is N,N-dimethylformamide; the molar ratio of the dianhydride monomer to the diamine monomer is 1:1.03;

[0089] (2) Drop the polyamic acid solution into deionized water to precipitate polyamic acid powder, and obtain polyimide after gradient temperature-rising thermal imidization;

[0090] The process of gradient temperature-rising thermal imidization is as follows: the heating rate is 4 °C / min, heat up from room temperature to 75 °C and hold for 0.5 h, then heat up to 100 °C and hold for 1.4 h, then heat up to 140 °C and hold for 1.2 h, then heat up to 193 °C and hold for 1.3 h, then heat up to 241 °C and hold for 1.3 h, then heat up to 267 °C and hold for 1.2 h;

[0091] (3) Perform primary pyrolysis on the polyimide in an argon atmosphere. The product is sequentially etched with acid, washed, and dried to obtain primary carbonized polyimide; the heating rate of primary pyrolysis is 6 °C / min; the primary pyrolysis temperature is 1000 °C and the time is 1.7 h; the acid etching is carried out using a hydrofluoric acid solution with a mass concentration of 8 wt%, and the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol;

[0092] (4) After grinding the primary carbonized polyimide, it is pyrolyzed again under an argon atmosphere. After the product is etched with acid, washed, and dried in sequence, the electrode material for fuel cells is obtained. The heating rate for the second pyrolysis is 3 °C / min, the second pyrolysis temperature is 780 °C, and the time is 3.8 h. The acid etching is carried out using a hydrofluoric acid solution with a mass concentration of 8 wt%. The washing is first done by washing 3 times with deionized water and then 2 times with absolute ethanol. The specific surface area and pore volume of the product are tested by nitrogen adsorption experiments, and its conductivity is tested by a four-probe tester. The specific surface area is 1242 m 2 g -1 , and the pore volume is 0.67 cm 3 g -1 ; the conductivity is 19.5 Scm -1 .

[0093] Comparative Example 1

[0094] A preparation method of an electrode material for fuel cells includes the following steps:

[0095] (1) Add the diamine monomer into an organic solvent. Under continuous stirring, add the dianhydride monomer into the organic solvent in 3 portions at intervals of 5 minutes. After the addition of the dianhydride monomer is completed, stir and react for 3.6 h, then add amino-POSS and continue to react for 6 h to form a polyamic acid solution. The mass of amino-POSS is 3.4 wt% of the sum of the masses of the dianhydride monomer and the diamine monomer; the stirring rate is 200 r / min;

[0096] The dianhydride monomer is selected from a mixture of pyromellitic dianhydride and 3,3',4,4'-biphenyltetracarboxylic dianhydride with a molar ratio of 2:1; the diamine monomer is selected from 4,4'-diaminodiphenyl ether; the amino-POSS is octaaminophenylcage silsesquioxane; the organic solvent is N,N-dimethylformamide; the molar ratio of the dianhydride monomer to the diamine monomer is 1:1.03;

[0097] (2) Drop the polyamic acid solution into deionized water to precipitate polyamic acid powder, and obtain polyimide after gradient heating thermal imidization;

[0098] The process of gradient heating thermal imidization is as follows: the heating rate is 4 °C / min. Heat from room temperature to 75 °C and keep warm for 0.5 h, then heat to 100 °C and keep warm for 1.4 h, then heat to 140 °C and keep warm for 1.2 h, then heat to 193 °C and keep warm for 1.3 h, then heat to 241 °C and keep warm for 1.3 h, then heat to 267 °C and keep warm for 1.2 h;

[0099] (3) The polyimide is subjected to primary pyrolysis in an argon atmosphere. The product is successively etched with acid, washed, and dried to obtain primary carbonized polyimide. The heating rate of the primary pyrolysis is 3 °C / min; the primary pyrolysis temperature is 780 °C, and the time is 3.8 h. The acid etching is carried out using a hydrofluoric acid solution with a mass concentration of 8 wt%. The washing is first done by washing 3 times with deionized water and then 2 times with absolute ethanol;

[0100] (4) After the primary carbonized polyimide is ground, it is pyrolyzed again in an argon atmosphere. The product is successively etched with acid, washed, and dried, and then the electrode material for fuel cells is obtained. The heating rate of the secondary pyrolysis is 6 °C / min, the secondary pyrolysis temperature is 1000 °C, and the time is 1.7 h. The acid etching is carried out using a hydrofluoric acid solution with a mass concentration of 8 wt%. The washing is first done by washing 3 times with deionized water and then 2 times with absolute ethanol. The specific surface area and pore volume of the product are tested by nitrogen adsorption experiments, and its conductivity is tested by a four-probe tester. The specific surface area is 423 m 2 g -1 , and the pore volume is 0.25 cm 3 g -1 ; the conductivity is 5.6 S cm -1 .

[0101] Comparative Example 2

[0102] A preparation method of an electrode material for fuel cells includes the following steps:

[0103] (1) The diamine monomer is added to an organic solvent. Under continuous stirring, the dianhydride monomer is added to the organic solvent in 3 portions at intervals of 5 minutes. After the addition of the dianhydride monomer is completed, the mixture is stirred and reacted for 3.6 h, and then amino-POSS is added and the reaction continues for 6 h to form a polyamic acid solution. The mass of amino-POSS is 3.4 wt% of the sum of the masses of the dianhydride monomer and the diamine monomer; the stirring rate is 200 r / min;

[0104] The dianhydride monomer is selected from a mixture of pyromellitic dianhydride and 3,3',4,4'-biphenyltetracarboxylic dianhydride with a molar ratio of 2:1. The diamine monomer is selected from 4,4'-diaminodiphenyl ether. The amino-POSS is octaaminophenylcage silsesquioxane. The organic solvent is N,N-dimethylformamide. The molar ratio of the dianhydride monomer to the diamine monomer is 1:1.03;

[0105] (2) The polyamic acid solution is dropped into deionized water to precipitate polyamic acid powder, and polyimide is obtained after gradient heating and thermal imidization;

[0106] The gradient heating thermal imidization process is as follows: the heating rate is 4 °C / min, heat up from room temperature to 75 °C and hold for 0.5 h, then heat up to 100 °C and hold for 1.4 h, then heat up to 140 °C and hold for 1.2 h, then heat up to 193 °C and hold for 1.3 h, then heat up to 241 °C and hold for 1.3 h, then heat up to 267 °C and hold for 1.2 h;

[0107] (3)Carry out primary pyrolysis on the polyimide under an argon atmosphere. The product is successively washed and dried to obtain primary carbonized polyimide; the heating rate of primary pyrolysis is 6 °C / min; the primary pyrolysis temperature is 1000 °C and the time is 1.7 h; the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol;

[0108] (4)After grinding the primary carbonized polyimide, pyrolyze it again under an argon atmosphere. The product is successively etched with acid, washed and dried to obtain the electrode material for fuel cells; the heating rate of the second pyrolysis is 3 °C / min, the second pyrolysis temperature is 780 °C and the time is 3.8 h; the acid etching is carried out with a hydrofluoric acid solution with a mass concentration of 8 wt%, and the washing is to wash 3 times with deionized water first, and then wash 2 times with absolute ethanol. The specific surface area and pore volume of the product are tested by nitrogen adsorption experiment, and its conductivity is tested by a four-probe tester. The specific surface area is 652 m 2 g -1 , the pore volume is 0.41 cm 3 g -1 ; the conductivity is 10.3 Scm -1 .

[0109] As can be seen from the above embodiments, the use of polyimide as a precursor material enables the preparation of self-doped carbon materials. Polyimide is a low-cost engineering plastic with a rigid aromatic backbone, which is easy to carbonize, has a high carbon yield, and is easier to dope with a more uniform doping effect. The amino group in POSS plays a role in nitrogen doping, greatly changing the chemical properties of carbon nanomaterials, thereby improving the performance of carbon nanomaterials; at the same time, the unique hollow closed cage structure of POSS undergoes volume shrinkage during calcination, introducing a porous structure. The SiOC (such as SiO2) structure formed by the transformation of POSS therein will be corroded by hydrofluoric acid, further improving the porous structure of carbon. A two-step pyrolysis method is used to prepare carbon materials. First, polyimide is carbonized at a higher temperature. On the one hand, it promotes the rapid carbonization and shaping of polyimide, especially the POSS structure, preventing the collapse of the structure during subsequent carbonization; on the other hand, the higher temperature promotes the pyrolysis of the POSS structure and the formation of the SiOC (such as SiO2) structure. After acid etching, the temperature is reduced from a higher temperature to a lower carbonization temperature to further carbonize the material and promote the formation of a porous structure. The POSS-modified polyimide carbon material prepared by the two-step method has a large specific surface area and a rich pore structure, which is beneficial to the improvement of the electrical conductivity of the carbon material. Compared with Example 7, Comparative Example 1 uses a conventional stepwise heating process for carbonization. The stepwise heating process cannot quickly form the structure of POSS and is prone to collapse during the heating process, which is not conducive to the increase of the specific surface area and conductivity of the carbon material. Comparative Example 2 shows that, compared with the common one-step acid etching process in the art, the first acid etching can promote the exposure of internal silicon oxides, which is not only beneficial to the second acid etching but also promotes the low-temperature carbonization process and is beneficial to the increase of the specific surface area.

[0110] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other. For the solutions disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For the relevant parts, reference can be made to the description in the method part. The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A preparation method of an electrode material for a fuel cell, characterized in that, It includes the following steps: (1) Add dianhydride monomers and diamine monomers into an organic solvent. After stirring and reacting for a period of time, add amino-POSS and continue the reaction to generate a polyamic acid solution; the mass of amino-POSS is 0.1-5 wt% of the sum of the masses of dianhydride monomers and diamine monomers; (2) Drop the polyamic acid solution into deionized water to precipitate polyamic acid powder, and obtain polyimide after gradient temperature rise and thermal imidization; (3) Carry out primary pyrolysis of the polyimide in an inert gas atmosphere. The product is successively etched with acid, washed, and dried to obtain primary carbonized polyimide; the primary pyrolysis temperature is 900-1200 °C, the time is 0.5-2 h; the primary pyrolysis heating rate is 5-10 °C / min; (4) Grind the primary carbonized polyimide and pyrolyze it again in an inert gas atmosphere. The product is successively etched with acid, washed, and dried to obtain the electrode material for fuel cells; the temperature for the second pyrolysis is 500-800 °C, the time is 2-5 h; the heating rate for the second pyrolysis is 1-5 °C / min; in steps (3) and (4), the acid etching is carried out using a hydrofluoric acid solution, and the mass concentration of the hydrofluoric acid solution is 5-15 wt%.

2. The preparation method of an electrode material for a fuel cell according to claim 1, characterized in that, In step (1), the dianhydride monomer is selected from one or more of pyromellitic dianhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, diphenyl sulfone-3,4,3',4'-tetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl) sulfide dianhydride, 2,2'-bis(3,4-dicarboxylic) hexafluoropropane dianhydride, 4,4'-hexafluoroisopropyl phthalic anhydride, 2,3,3',4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl) methane dianhydride, 2,2-bis(3,4-dicarboxyphenyl) propane dianhydride, m-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, p-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, 1,3-bis(3,4-dicarboxyphenoxy) benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy) benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy) biphenyl dianhydride, 2,2-bis[(3,4-dicarboxyphenoxy)phenyl] propane dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride.

3. The preparation method of an electrode material for a fuel cell according to claim 1, wherein, In step (1), the diamine monomer is selected from one or more of p-phenylenediamine, m-phenylenediamine, 3,3'-dimethylbenzidine, 2,2'-dimethylbenzidine, 2,4-diaminotoluene, 2,6-diaminotoluene, 3,5-diaminobenzoic acid, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-dicarboxy-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, 4,4'-diaminobenzanilide, 3,3'-dimethoxybiphenylamine, 2,2'-dimethoxybiphenylamine, 3,3'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diamino-4,4'-dichlorobenzophenone, 3,3'-diamino-4,4'-dimethoxybenzophenone.

4. The preparation method of an electrode material for a fuel cell according to claim 1, characterized in that, In step (1), the amino-functional POSS is one or more of octaaminophenyl silsesquioxane, octaaminopropyl silsesquioxane, aminopropylisobutyl silsesquioxane, aminopropylisooctyl silsesquioxane.

5. The preparation method of an electrode material for a fuel cell according to claim 1, characterized in that, In step (1), the molar ratio of the dianhydride monomer to the diamine monomer is 1:(1 - 1.05).

6. The preparation method of an electrode material for a fuel cell according to claim 1, characterized in that, In steps (3) and (4), the inert gas is at least one of argon, nitrogen, and helium.

7. The preparation method of an electrode material for a fuel cell according to claim 1, characterized in that In steps (3) and (4), the cleaning is first to wash 2 - 4 times with deionized water, and then wash 1 - 3 times with absolute ethanol.

8. An electrode material for a fuel cell, characterized in that: Prepared by the preparation method of an electrode material for a fuel cell according to any one of claims 1 - 7.