CN103566960B - A kind of fuel-cell catalyst and preparation thereof and application - Google Patents

Abstract

The invention provides a fuel cell catalyst and its preparation and application. The fuel cell catalyst is characterized in that, wherein, the active component is N, N'-disalicylaldehyde ethylenediamine and a transition metal salt; the N, N'-disalicylaldehyde ethylenediamine and a transition metal The mass ratio of the transition metal in the salt is 1:1 to 1:0.015; the ratio of the weight of the carbon material to the sum of the weight of N,N'-disalicylaldehyde ethylenediamine in the active component and the transition metal in the transition metal salt For 40-90: 10-60. The invention can significantly reduce the cost of the fuel cell and improve the catalytic activity.

Description

A kind of fuel cell catalyst and its preparation and application

technical field

The invention belongs to the field of non-precious metal catalysts for fuel cells, in particular to a carbon-supported N, N'-disalicylaldehyde ethylenediamine cobalt (Co-salen/C) fuel cell catalyst and its preparation method and application.

Background technique

A fuel cell is a device that directly converts chemical energy present in fuels and oxidants into electrical energy. It has the advantages of high energy conversion efficiency, rapid startup at room temperature, and environmental friendliness. It is widely used in military, space, power plants, motor vehicles, and mobile devices. , residential and other fields have a wide range of applications. Among them, the fuel cells with proton exchange membrane as the electrolyte layer are called proton exchange membrane fuel cells (PEMFCs). Compared with other fuel cells, PEMFCs can start up quickly at room temperature and can quickly change the output power according to the load requirements, making them ideal alternative power sources for the most promising future electric vehicles, distributed power stations, backup power sources, and portable appliances.

However, the commercialization of fuel cells has encountered many constraints. The key reason is that the effective catalysts for the anode and cathode are platinum (Pt)-based metal catalysts. Pt is expensive and lack of resources seriously restricts its commercial scale application. . Therefore, reducing the loading of Pt in fuel cells and developing non-precious metal catalysts have become the current focus of attention and the main direction of low-temperature fuel cell catalyst research. In the short term, it is feasible to reduce the Pt loading, but in the long run, it is a better choice to find non-precious metal catalysts that can replace Pt. Many defects and deficiencies that proton exchange membrane fuel cells have can be avoided when the fuel cells are operated under alkaline medium (OH ⁻ ) conditions. Under alkaline conditions, the oxidation of fuel (H ₂ , methanol) on the anode and the reduction of oxygen (O ₂ ) on the cathode will become easier, and the corrosion resistance of many materials in alkaline environments is much better than that in In acidic medium, therefore, inexpensive non-Pt electrocatalysts such as Ag, Ni, Co, Fe, MnO2, etc. can be used to replace expensive Pt catalysts, thereby greatly reducing the manufacturing cost of fuel cells.

At present, the research of non-precious metal catalysts for fuel cells mainly focuses on transition metal oxides, sulfides, transition metal carbonyl compounds and transition metal macrocyclic compounds [Electrochim.Acta, 41(1996) 1689; J.ElectrochemSoc, 141(1994 ) 41; Int J Hydrogen Energy, 25 (2000) 255]. While high-temperature heat-treated carbon-supported transition metal N-doped materials are considered to be the most promising oxygen reduction catalysts, some of them have shown oxygen reduction activities close to or even higher than commercial Pt/C catalysts [EnergyEnviron.Sci., 4 , 3167 (2011)]. Among them, the structure of the transition metal center ion and the nitrogen-containing ligand is considered to be the key factor determining the activity of the catalyst [Electrochim.Acta52, 2562 (2007)].

Chinese patent CN10657921A reports a nitrogen-containing aromatic compound and transition metal composite supported by nano-carbon particles, and Chinese patent CN102021677A reports a nano-carbon fiber containing transition metal and nitrogen, all of which form the coordination of transition metal and nitrogen. compounds, showing good oxygen reduction activity. However, the structure and catalytic mechanism of carbon-supported transition metal and N-doped catalysts are still not very clear, and their activity is still far behind that of Pt catalysts.

Contents of the invention

The technical problem to be solved by this invention is to provide a kind of carbon-loaded N, N'-cobalt (Co-salen/C) fuel cell catalyst and its preparation method and application. The catalyst is a non-platinum catalyst, which can significantly The cost of the fuel cell is reduced; the preparation method is simple, easy to operate, low in cost, suitable for industrial production, and has good application prospects.

In order to solve the above technical problems, the present invention provides a fuel cell catalyst, which is characterized in that it is made of raw materials including carbon materials and active components, wherein the active component is N, N'-disalicylaldehyde Diamine and transition metal salt; the mass ratio of the transition metal in the N,N'-disalicylaldehyde ethylenediamine and the transition metal salt is 1:1～1:0.015; the weight of the carbon material and the N in the active component , The weight sum ratio of N'-disalicylaldehyde ethylenediamine and the transition metal in the transition metal salt is 40-90:10-60.

Preferably, the carbon material is at least one of VulcanXC-72, BP2000, carbon nanotubes, carbon nanocages, carbon nanofibers and graphene.

Preferably, the transition metal salt is a cobalt salt and other transition metal salts in a mass ratio of 1:0-1:1.

More preferably, the cobalt salt is cobalt sulfate, cobalt nitrate, cobalt chloride, cobalt acetate or cobalt ethyl acetate.

More preferably, the other transition metal salts are ammonium vanadate, ammonium molybdate, sodium tungstate or cerium nitrate.

The present invention also provides the preparation method of above-mentioned fuel cell catalyst, it is characterized in that, concrete steps are:

The first step: put the carbon material and the active component in the mortar according to the proportion, add the solvent, fully grind until the solvent is completely evaporated, and dry in vacuum to obtain the catalyst precursor;

The second step: the catalyst precursor obtained in the first step is roasted at 600-1000° C. for 2-4 hours at a rate of 20° C./min under the protection of an inert gas atmosphere to obtain a fuel cell catalyst.

Preferably, the solvent is water, methanol, ethanol or chloroform.

Preferably, the inert gas is argon or nitrogen.

The present invention also provides a method for preparing a membrane-electrode assembly for a fuel cell using the above-mentioned fuel cell catalyst, characterized in that the specific steps are: dispersing the fuel cell catalyst into water, ethanol or isopropanol solution, ultrasonically Finally, obtain the ink solution of the catalyst; transfer the ink solution of the catalyst to the glassy carbon (GC) electrode to dry naturally to form a catalyst layer, then mix the methanol solution and the Nafion solution as a binding agent, and drop the binding agent on the The catalyst layer on the glassy carbon (GC) electrode is naturally dried to obtain a membrane-electrode assembly for a fuel cell.

Preferably, the fuel cell is a direct alkaline fuel cell using methanol, ethanol, propanol, glycerol or dimethyl ether as liquid fuel, a hydrogen-air (O ₂ ) alkaline fuel cell, a zinc-air battery or a microbial The fuel cell.

Preferably, the mass ratio of the methanol solution to the Nafion solution is 1:5-1:100.

Preferably, the fuel cell catalyst loading in the fuel cell membrane electrode assembly is 80 μg-1500 μg/cm ² .

Compared with prior art, the beneficial effect of the present invention is:

(1) The present invention is a non-platinum catalyst, which can significantly reduce the cost of the fuel cell, and form a Co-Nx-C composite structure by modifying the active metal with a nitride at a high temperature, thereby improving the catalytic activity;

(2) The preparation method of the present invention is simple, easy to operate, low in cost, suitable for industrial production, and has good application prospects.

Description of drawings

Fig. 1 is the polarization curve (wherein: Co _- salen/C-700 corresponds to Example 14, Co-salen/C-600 corresponds to Example 15, Co -salen/C-800 corresponds to Example 16, Co-salen/C-900 corresponds to Example 17, and Co-salen/C-1000 corresponds to Example 18); Fig. 2 is that fuel cell catalysts with different loads are saturated in O ₂ Polarization curves in 0.1M KOH solution (where: Co-salen/C-700-80μg/cm2 corresponds to Example 14, Co-salen/C-700-200μg/cm2 corresponds to Example 19, Co-salen/C- 700-400 μg/cm Corresponding to Example 20, Co-salen/C-700-800 μg/cm Corresponding to Example 21);

detailed description

In order to make the present invention more comprehensible, preferred embodiments are described in detail as follows. All mass percentages in Examples 1-13 are calculated based on the sum of the mass of N, N'-disalicylaldehyde ethylenediamine in the active component and the transition metal in the transition metal salt.

Example 1

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and transition metal Co salt; VulcanXC-72R carbon powder The mass percent of is 80wt%, and the sum of the mass percents of N, N'-disalicylaldehyde ethylenediamine and the transition metal Co in the transition metal Co salt in the active component is 20wt%, and 20wt% of the active component includes 10wt% Co and 10wt% N, N'-disalicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O. The preparation method of the fuel cell catalyst is: weighing 0.0.0477g CoSO ₄ ·7H ₂ O, 0.0100g N,N'-disalicylaldehyde ethylenediamine and 0.0800g VulcanXC-72R carbon powder and placing them in an agate mortar. Add 20ml of analytical pure methanol, fully grind until the methanol is completely volatilized, put the agate mortar and the mixture in a vacuum oven at 60°C for 1 h in vacuum to obtain a catalyst precursor, and place the obtained catalyst precursor in a quartz boat, Under the protection of _N2 atmosphere, the fuel cell catalyst (Co-Salen/C-700 catalyst) was obtained by calcining and reducing for 2 hours at a temperature increase rate of 20 °C/min to 700 °C.

Example 2

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and transition metal Co salt; VulcanXC-72R carbon powder The mass percentage of is 60wt%, the sum of the mass percentages of N, N'-disalicylaldehyde ethylenediamine and the transition metal Co salt in the transition metal Co salt is 40wt%, and 40wt% of the active component includes 15wt% Co and 25wt% N, N'-disalicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O. The preparation method of the fuel cell catalyst is: weighing 0.0716g CoSO ₄ ·7H ₂ O, 0.0250g N,N'-disalicylaldehyde ethylenediamine and 0.9600g VulcanXC-72R carbon powder and placing them in an agate mortar. Add 20ml of analytical pure methanol, fully grind until the methanol is completely volatilized, put the agate mortar and the mixture in a vacuum oven at 60°C for 1 h in vacuum to obtain a catalyst precursor, and place the obtained catalyst precursor in a quartz boat, Under the protection of _N2 atmosphere, the fuel cell catalyst (Co-Salen/C-700 catalyst) was obtained by calcining and reducing for 2 hours at a temperature increase rate of 20 °C/min to 700 °C.

Example 3

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and transition metal Co salt; VulcanXC-72R carbon powder The mass percent of is 60wt%, and the sum of the mass percents of N, N'-disalicylaldehyde ethylenediamine and the transition metal Co salt in the transition metal Co salt in the active component is 40wt%, and 40wt% of the active component includes 25wt% Co and 15wt% N, N'-disalicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O. The preparation method of the fuel cell catalyst is: weighing 0.1193g CoSO ₄ ·7H ₂ O, 0.0150g N,N'-disalicylaldehyde ethylenediamine and 0.0600g VulcanXC-72R carbon powder and placing them in an agate mortar. Add 20ml of analytical pure methanol, fully grind until the methanol is completely volatilized, put the agate mortar and the mixture in a vacuum oven at 60°C for 1 h in vacuum to obtain a catalyst precursor, and place the obtained catalyst precursor in a quartz boat, Under the protection of _N2 atmosphere, the fuel cell catalyst (Co-Salen/C-700 catalyst) was obtained by calcining and reducing for 2 hours at a temperature increase rate of 20 °C/min to 700 °C.

Example 4

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and transition metal Co salt; VulcanXC-72R carbon powder The mass percentage of is 60wt%, the sum of the mass percentages of N, N'-disalicylaldehyde ethylenediamine and the transition metal Co salt in the transition metal Co salt is 40wt%, and 40wt% of the active component includes 15wt% Co and 25wt% N, N'-disalicylaldehyde ethylenediamine, wherein the Co salt used is Co(NO ₃ ) ₂ ·6H ₂ O. The preparation method of the fuel cell catalyst is: weighing 0.0741g Co(NO ₃ ) ₂ ·6H2O, 0.0250g N,N'-disalicylaldehyde ethylenediamine and 0.0600g VulcanXC-72R carbon powder and placing them in an agate mortar. Add 20ml of analytical pure methanol, fully grind until the methanol is completely volatilized, put the agate mortar and the mixture in a vacuum oven at 60°C for 1 h in vacuum to obtain a catalyst precursor, and place the obtained catalyst precursor in a quartz boat, Under the protection of _N2 atmosphere, the fuel cell catalyst (Co-Salen/C-700 catalyst) was obtained by calcining and reducing for 2 hours at a temperature increase rate of 20 °C/min to 700 °C.

Example 5

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and transition metal Co salt; VulcanXC-72R carbon powder The mass percentage of is 60wt%, the sum of the mass percentages of N, N'-disalicylaldehyde ethylenediamine and the transition metal Co salt in the transition metal Co salt is 40wt%, and 40wt% of the active component includes 15wt% Co and 25wt% N, N'-disalicylaldehyde ethylenediamine, wherein the Co salt used is cobalt acetate.

The preparation method of the fuel cell catalyst is as follows: weighing 0.0451g of cobalt acetate, 0.0250g of N,N'-disalicylaldehyde ethylenediamine and 0.0600g of VulcanXC-72R carbon powder and placing them in an agate mortar. Add 20ml of analytical pure methanol, fully grind until the methanol is completely volatilized, put the agate mortar and the mixture in a vacuum oven at 60°C for 1 h in vacuum to obtain a catalyst precursor, and place the obtained catalyst precursor in a quartz boat, Under the protection of _N2 atmosphere, the fuel cell catalyst (Co-Salen/C-700 catalyst) was obtained by calcining and reducing for 2 hours at a temperature increase rate of 20 °C/min to 700 °C.

Example 6

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and Co salt and W salt; VulcanXC-72R carbon The mass percentage of the powder is 60wt%, the sum of the mass percentages of N, N'-disalicylaldehyde ethylenediamine and Co salt and W salt in the transition metal Co and W in the active component is 40wt%, and the active component of 40wt% Include 10wt% Co, 5wt% W and 25wt% N,N'-disalicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O, and the W salt used is sodium tungstate.

The preparation method of the fuel cell catalyst is as follows: Weigh 0.0477g CoSO ₄ 7H ₂ O, 0.0250g N, N'-disalicylaldehyde ethylenediamine, 0.0090g sodium tungstate and 0.0600g VulcanXC-72R carbon powder and place them in an agate mortar middle. Add 20ml of methanol of analytical grade and grind thoroughly until the methanol is completely volatilized. Put the agate mortar and its mixture in a vacuum oven at 60°C for 1 h to obtain a catalyst precursor, place the obtained catalyst precursor in a quartz boat, and raise the temperature at 20°C/min under the protection of _N2 atmosphere The fuel cell catalyst (Co-Salen/C-700 catalyst) was obtained by calcining and reducing for 2 hours at a rate increased to 700°C.

Example 7

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and Co salt and Ce salt; VulcanXC-72R carbon The mass percentage of the powder is 60wt%, the sum of the mass percentages of N, N'-disalicylaldehyde ethylenediamine and Co salt and the transition metals Co and Ce in the Ce salt in the active component is 40wt%, and the active component of 40wt% Include 10wt% Co, 5wt% Ce and 25wt% N,N'-disalicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O, and the Ce salt used is cerium nitrate.

The preparation method of the fuel cell catalyst is as follows: Weigh 0.0716g CoSO ₄ ·7H ₂ O, 0.0250g N, N'-disalicylaldehyde ethylenediamine, 0.0150g cerium nitrate and 0.0600g VulcanXC-72R carbon powder and place them in an agate mortar . Add 20ml of methanol of analytical grade and grind thoroughly until the methanol is completely volatilized. Put the agate mortar and its mixture in a vacuum oven at 60°C for 1 h to obtain a catalyst precursor, place the obtained catalyst precursor in a quartz boat, and raise the temperature at 20°C/min under the protection of _N2 atmosphere The fuel cell catalyst (Co-Salen/C-700 catalyst) was obtained by calcining and reducing for 2 hours at a rate increased to 700°C.

Example 8

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and Co salt; The quality of VulcanXC-72R carbon powder The percentage is 60wt%, the sum of the mass percentages of N, N'-disalicylaldehyde ethylenediamine and the transition metal Co in the Co salt in the active component is 40wt%, and 40wt% of the active component contains 15wt% Co and 25wt% % of N,N,-disalicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O. The preparation method of the fuel cell catalyst is: weighing 0.0716g CoSO ₄ ·7H ₂ O, 0.0250g N,N'-disalicylaldehyde ethylenediamine and 0.0600g VulcanXC-72R carbon powder and placing them in an agate mortar. Add 20ml of methanol of analytical grade and grind thoroughly until the methanol is completely volatilized. Put the agate mortar and its mixture in a vacuum oven at 60°C for 1 h to obtain a catalyst precursor, place the obtained catalyst precursor in a quartz boat, and raise the temperature at 20°C/min under the protection of _N2 atmosphere The rate is increased to 600° C. and calcined and reduced for 2 hours to obtain the required fuel cell catalyst (Co-Salen/C-600 catalyst).

Example 9

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and Co salt; The quality of VulcanXC-72R carbon powder Percentage is 60wt%, the mass percent of the transition metal Co in N, N'-disalicylaldehyde ethylenediamine and Co salt in the active component is 40wt%, and the active component of 40wt% contains the Co of 15wt% and the Co of 25wt% N, N'-disalicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O. The preparation method of the fuel cell catalyst is: weighing 0.0716g CoSO ₄ ·7H ₂ O, 0.0250g N,N'-disalicylaldehyde ethylenediamine and 0.0600g VulcanXC-72R carbon powder and placing them in an agate mortar. Add 20mi of analytically pure methanol and grind until the methanol is completely volatilized. Put the agate mortar and its mixture in a vacuum oven at 60°C for 1 h to obtain a catalyst precursor, place the obtained catalyst precursor in a quartz boat, and raise the temperature at 20°C/min under the protection of _N2 atmosphere The rate was increased to 800° C. and calcined and reduced for 2 hours to obtain the required fuel cell catalyst (Co-Salen/C-800 catalyst).

Example 10

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and Co salt; The quality of VulcanXC-72R carbon powder Percentage is 60wt%, the mass percent of the transition metal Co in N, N'-disalicylaldehyde ethylenediamine and Co salt in the active component is 40wt%, and the active component of 40wt% contains the Co of 15wt% and the Co of 25wt% N, N'-disalicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O. The preparation method of the fuel cell catalyst is: weighing 0.0716g CoSO ₄ ·7H ₂ O, 0.0250g N,N'-disalicylaldehyde ethylenediamine and 0.0600g VulcanXC-72R carbon powder and placing them in an agate mortar. Add 20ml of methanol of analytical grade and grind thoroughly until the methanol is completely volatilized. Put the agate mortar and its mixture in a vacuum oven at 60°C for 1 h to obtain a catalyst precursor, place the obtained catalyst precursor in a quartz boat, and raise the temperature at 20°C/min under the protection of _N2 atmosphere The rate was increased to 900° C. and calcined and reduced for 2 hours to obtain the required fuel cell catalyst (Co-Salen/C-900 catalyst).

Example 11

A kind of fuel cell catalyst, adopts the raw material that comprises VulcanXC-72R carbon powder and active component to make, and described active component is N, N'-disalicylaldehyde ethylenediamine and Co salt; The quality of VulcanXC-72R carbon powder Percentage is 60wt%, the mass percent of the transition metal Co in N, N'-disalicylaldehyde ethylenediamine and Co salt in the active component is 40wt%, and the active component of 40wt% contains the Co of 15wt% and the Co of 25wt% N, N'-disalicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O. The preparation method of the fuel cell catalyst is: weighing 0.0716g CoSO ₄ ·7H ₂ O, 0.0250g N,N'-disalicylaldehyde ethylenediamine and 0.0600g VulcanXC-72R carbon powder and placing them in an agate mortar. Add 20ml of methanol of analytical grade and grind thoroughly until the methanol is completely volatilized. Put the agate mortar and its mixture in a vacuum oven at 60°C for 1 h to obtain a catalyst precursor, place the obtained catalyst precursor in a quartz boat, and raise the temperature at 20°C/min under the protection of _N2 atmosphere The rate was increased to 1000° C. and calcined and reduced for 2 hours to obtain the required fuel cell catalyst (Co-Salen/C-1000 catalyst).

Example 12

A kind of fuel cell catalyst, adopts the raw material that comprises carbon nanotube and active component to make, and described active component is N, N'disalicylaldehyde ethylenediamine and Co salt; The mass percent of carbon nanotube is 60wt%, The mass percentage of N, N'-disalicylaldehyde ethylenediamine and the transition metal Co in the Co salt in the active component is 40wt%, and the 40wt% active component contains 15wt% Co and 25wt% N, N'- Disalicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O. The preparation method of the fuel cell catalyst is: weighing 0.0716g CoSO ₄ ·7H ₂ O, 0.0250g N,N'-disalicylaldehyde ethylenediamine and 0.0600g carbon nanotubes and placing them in an agate mortar. Add 20ml of methanol of analytical grade and grind thoroughly until the methanol is completely volatilized. Put the agate mortar and the mixture therein into a vacuum oven at 60°C for 1 h to obtain a catalyst precursor, put the catalyst precursor in a quartz boat, and raise the temperature at a rate of 20°C/min under the protection of _N2 atmosphere Calcination and reduction treatment at up to 700° C. for 2 hours to obtain the required fuel cell catalyst (Co-salen/CNT-700 catalyst).

Example 13

A kind of fuel cell catalyst, adopts the raw material that comprises graphene and active component to be made, and described active component is N, N'-disalicylaldehyde ethylenediamine and Co salt; The mass percent of graphene is 60wt%, activity The mass percentage of N, N'-disalicylaldehyde ethylenediamine and the transition metal Co in the Co salt is 40wt%, and the 40wt% active component contains 15wt% Co and 25wt% N, N'-di Salicylaldehyde ethylenediamine, wherein the Co salt used is CoSO ₄ ·7H ₂ O.

The preparation method of the fuel cell catalyst is: weighing 0.0716g CoSO ₄ ·7H ₂ O, 0.0250g N,N'-disalicylaldehyde ethylenediamine and 0.0600g graphene and placing them in an agate mortar. Add 20ml of methanol of analytical grade and grind thoroughly until the methanol is completely volatilized. Put the agate mortar and its mixture in a vacuum oven at 60°C for 1 h to obtain a catalyst precursor, place the obtained catalyst precursor in a quartz boat, and raise the temperature at 20°C/min under the protection of _N2 atmosphere The rate was increased to 700° C. and calcined and reduced for 2 hours to obtain the required fuel cell catalyst (Co-salen/Graphene-700 catalyst).

Example 14

Disperse 4 mg of the fuel cell catalyst in Example 2 into 2 ml of 99.7% isopropanol solution, and obtain a catalyst solution under the action of ultrasound. Use a micropipette to transfer 10 μl of the above catalyst solution to a GC electrode with a diameter of 0.2475 cm ² , and let it dry naturally to form a catalyst layer. Mix 5% Nafion solution and 99.5% methanol solution at a mass ratio of 1:100 as a binder, take a drop of binder and drop it on the catalyst layer on the glassy carbon (GC) electrode, and let it dry naturally. The loading capacity of the fuel cell catalyst was 80.8 μg/cm ² , and it was dried naturally to obtain a fuel cell membrane-electrode assembly.

Example 15

Disperse 4 mg of the fuel cell catalyst in Example 8 into 2 ml of 99.7% isopropanol solution, and obtain a catalyst solution under the action of ultrasound. Use a micropipette to transfer 10 μl of the above catalyst solution to a GC electrode with a diameter of 0.2475 cm ² , and let it dry naturally to form a catalyst layer. Mix 5% Nafion solution and 99.5% methanol solution at a mass ratio of 1:100 as a binder, take a drop of binder and drop it on the catalyst layer on the glassy carbon (GC) electrode, and let it dry naturally. The loading capacity of the fuel cell catalyst was 80.8 μg/cm ² , and it was dried naturally to obtain a fuel cell membrane-electrode assembly.

Example 16

Disperse 4 mg of the fuel cell catalyst in Example 9 into 2 ml of 99.7% isopropanol solution, and obtain a catalyst solution under the action of ultrasound. Use a micropipette to transfer 10 μl of the above catalyst solution to a GC electrode with a diameter of 0.2475 cm ² , and let it dry naturally to form a catalyst layer. Mix 5% Nafion solution and 99.5% methanol solution at a mass ratio of 1:100 as a binder, take a drop of binder and drop it on the catalyst layer on the glassy carbon (GC) electrode, and let it dry naturally. The loading amount of the fuel cell catalyst was 80.8 μg/crn ² , and it was dried naturally to obtain a membrane-electrode assembly for a fuel cell.

Example 17

Disperse 4 mg of the fuel cell catalyst in Example 10 into 2 ml of 99.7% isopropanol solution, and obtain a catalyst solution under the action of ultrasound. Use a micropipette to transfer 10 μl of the above catalyst solution to a GC electrode with a diameter of 0.2475 cm ² , and let it dry naturally to form a catalyst layer. Mix 5% Nafion solution and 99.5% methanol solution at a mass ratio of 1:100 as a binder, take a drop of binder and drop it on the catalyst layer on the glassy carbon (GC) electrode, and let it dry naturally. The loading capacity of the fuel cell catalyst was 80.8 μg/cm ² , and it was dried naturally to obtain a fuel cell membrane-electrode assembly.

Example 18

Disperse 4 mg of the fuel cell catalyst in Example 11 into 2 ml of 99.7% isopropanol solution, and obtain a catalyst solution under the action of ultrasound. Use a micropipette to transfer 10 μl of the above catalyst solution to a GC electrode with a diameter of 0.2475 cm ² , and let it dry naturally to form a catalyst layer. Mix 5% Nafion solution and 99.5% methanol solution at a mass ratio of 1:100 as a binder, take a drop of binder and drop it on the catalyst layer on the glassy carbon (GC) electrode, and let it dry naturally. The loading capacity of the fuel cell catalyst was 80.8 μg/cm ² , and it was dried naturally to obtain a fuel cell membrane-electrode assembly.

Example 19

Disperse 10 mg of the fuel cell catalyst in Example 2 into 2 ml of 99.7% isopropanol solution, and obtain a catalyst solution under the action of ultrasound. Use a micropipette to transfer 10 μl of the above catalyst solution to a GC electrode with a diameter of 0.2475 cm ² , and let it dry naturally to form a catalyst layer. Mix 5% Nafion solution and 99.5% methanol solution at a mass ratio of 1:100 as a binder, take a drop of binder and drop it on the catalyst layer on the glassy carbon (GC) electrode, and let it dry naturally. The loading amount of the fuel cell catalyst was 202.0 μg/cm ² , and it was dried naturally to obtain a fuel cell membrane-electrode assembly.

Example 20

Disperse 20 mg of the fuel cell catalyst in Example 2 into 2 ml of 99.7% isopropanol solution, and obtain a catalyst solution under the action of ultrasound. Use a micropipette to transfer 10 μl of the above catalyst solution to a GC electrode with a diameter of 0.2475 cm ² , and let it dry naturally to form a catalyst layer. Mix 5% Nafion solution and 99.5% methanol solution at a mass ratio of 1:100 as a binder, take a drop of binder and drop it on the catalyst layer on the glassy carbon (GC) electrode, and let it dry naturally. The loading amount of the fuel cell catalyst was 404.0 μg/cm ² , and it was dried naturally to obtain a fuel cell membrane-electrode assembly.

Example 21

Disperse 40 mg of the fuel cell catalyst in Example 2 into 2 ml of 99.7% isopropanol solution, and obtain a catalyst solution under the action of ultrasound. Use a micropipette to transfer 10 μl of the above catalyst solution to a GC electrode with a diameter of 0.2475 cm ² , and let it dry naturally to form a catalyst layer. Mix 5% Nafion solution and 99.5% methanol solution at a mass ratio of 1:100 as a binder, take a drop of binder and drop it on the catalyst layer on the glassy carbon (GC) electrode, and let it dry naturally. The loading capacity of the fuel cell catalyst was 808.1 μg/cm ² , and it was dried naturally to obtain a membrane-electrode assembly for a fuel cell.

The electrochemical performance of the membrane-electrode assembly in Examples 14-21 was tested by using the rotating ring disk technique (RDE) in the traditional three-electrode system. The electrolyte is 0.1M KOH, the working electrode is the membrane electrode combination in Examples 14-21, the reference electrode is a saturated calomel electrode, and the counter electrode is a Pt wire electrode. The polarization curves at room temperature are shown in Figure 1 and Figure 2.

It can be found from Fig. 1 and Fig. 2 that the fuel cell catalyst prepared in the present invention has higher activity and stability. The fuel cell catalyst prepared at 700℃ exhibited the best catalytic activity. The gas diffusion electrode prepared by it can produce obvious oxygen reduction current at 0.08V (relative to the standard hydrogen electrode) under 0.1MKOH electrolyte solution and saturated _O2 atmosphere, the half-wave potential is -0.02V, and the maximum limit diffusion current density is 3.4mAcm ^-2 . In addition, when the Co-salen/C load is 808.1 μg/cm ² , an obvious oxygen reduction current can be generated at 0.12V (relative to the standard hydrogen electrode), and the half-wave potential is 0.055V, which is shifted by about 35mV. The maximum limiting diffusion current has been increased by 25%.

Claims (7)

1. A catalyst for a fuel cell, characterized in that it is made from raw materials comprising carbon materials and active components, wherein the active components are N, N'-disalicylaldehyde ethylenediamine and transition metal salts; The mass ratio of N,N'-disalicylaldehyde ethylenediamine and the transition metal in the transition metal salt is 1:0.6~1:0.015; The weight sum ratio of the amine and the transition metal in the transition metal salt is 40:60. 2. The fuel cell catalyst according to claim 1, wherein the carbon material is at least one of VulcanXC-72, BP2000, carbon nanotubes, carbon nanocages, carbon nanofibers and graphene. 3. The fuel cell catalyst according to claim 1, wherein the transition metal salt is a cobalt salt and other transition metal salts in a mass ratio of 1:0 to 1:1. 4. The fuel cell catalyst according to claim 3, wherein the cobalt salt is cobalt sulfate, cobalt nitrate, cobalt chloride, cobalt acetate or cobalt ethyl acetate. 5. The fuel cell catalyst according to claim 3, wherein the transition metal salt is ammonium vanadate, ammonium molybdate, sodium tungstate or cerium nitrate. 6. A method for preparing fuel cell membrane-electrode assemblies using the fuel cell catalyst described in any one of claims 1-5, characterized in that, the specific steps are: dispersing the fuel cell catalyst into water, ethanol or In the isopropanol solution, the catalyst solution was obtained after ultrasonication; the catalyst solution was transferred to the glassy carbon electrode, and naturally dried to form a catalyst layer, and the methanol solution and the Nafion solution were mixed as a binder, and the binder was dropped on the The catalyst layer on the glassy carbon electrode is naturally dried to obtain a membrane-electrode assembly for a fuel cell. 7. fuel cell catalyst as claimed in claim 6 prepares the method in fuel cell membrane electrode assembly, it is characterized in that, described fuel cell is to take methanol, ethanol, propanol, glycerol or dimethyl ether as liquid fuel direct alkaline fuel cells, hydrogen-air alkaline fuel cells, zinc-air batteries or microbial fuel cells.