Oxygen vacancy regulation cobalt manganese oxide-covalent bonding nonporous polyarylene ether nitrile composite system and application thereof in high-temperature alkaline water electrolysis hydrogen production

Abstract

The invention relates to the related field of alkaline electrolytic water hydrogen production, in particular to an oxygen vacancy regulated cobalt manganese oxide-covalent bonding nonporous polyarylene ether nitrile composite system which comprises oxygen vacancy regulated cobalt manganese oxide and covalent bonding nonporous polyarylene ether nitrile. The oxygen vacancy regulated cobalt manganese oxide is anchored in the structure of the covalently bonded nonporous polyarylene ether nitrile through covalent cross-linking. By accurately regulating and controlling oxygen vacancies in the cobalt-manganese oxide, the electrocatalytic activity of the cobalt-manganese oxide is remarkably improved, and the hydrogen evolution overpotential is reduced, so that the composite system shows excellent catalytic performance in high-temperature alkaline water electrolysis hydrogen production, and the hydrogen evolution efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydrogen production by alkaline electrolysis of water, in particular to an oxygen vacancy regulated cobalt-manganese oxide-covalently bonded non-porous polyarylether nitrile composite system and its application in high-temperature alkaline electrolysis of water for hydrogen production. BACKGROUND

[0002] With the increasing demand for clean energy worldwide, hydrogen production by electrolysis of water has received extensive attention as a sustainable method. In the process of hydrogen production by electrolysis of water, the anodic oxygen evolution reaction (OER) and the cathodic hydrogen evolution reaction (HER) are two key steps. However, these two reactions usually require high overpotential, resulting in low energy efficiency. Therefore, it is of great significance to develop efficient electrocatalysts to reduce overpotential and improve the efficiency of hydrogen production by electrolysis of water.

[0003] Cobalt-manganese oxide has become a potential electrocatalyst material due to its abundant element reserves, good catalytic activity and stability. Studies have shown that by regulating the oxygen vacancies in cobalt-manganese oxide, its electronic structure and chemical activity can be significantly changed, thereby improving its electrocatalytic performance. For example, the presence of oxygen vacancies can introduce additional energy levels, act as specific reaction sites for certain molecules, promote electron transfer, enhance the electrical conductivity of the material, and thus improve the catalytic reaction rate.

[0004] On the other hand, covalently bonded non-porous polyarylether nitrile has excellent thermal stability, chemical stability and mechanical properties, and can maintain the integrity of its structure in the high-temperature, strong-alkaline environment of water electrolysis. By combining cobalt-manganese oxide with covalently bonded non-porous polyarylether nitrile, the advantages of both can be fully utilized, and a high-temperature alkaline water electrolysis catalyst with excellent performance can be expected. However, there is currently little research on this composite system, and how to effectively combine the two, as well as optimizing the composition and structure of the composite system to improve its performance in high-temperature alkaline water electrolysis, remains a problem to be solved. SUMMARY

[0005] The purpose of the present application is to solve the problems existing in the prior art and to provide an oxygen vacancy regulated cobalt-manganese oxide-covalently bonded non-porous polyarylether nitrile composite system.

[0006] An oxygen vacancy regulated cobalt-manganese oxide-covalently bonded non-porous polyarylether nitrile composite system, comprising oxygen vacancy regulated cobalt-manganese oxide and covalently bonded non-porous polyarylether nitrile, wherein the oxygen vacancy regulated cobalt-manganese oxide is anchored in the structure of the covalently bonded non-porous polyarylether nitrile through covalent cross-linking.

[0007] Further, the oxygen vacancy regulated cobalt manganese oxide is prepared by co-precipitation method to prepare cobalt manganese precursor, and then is obtained by heat treatment in a reducing gas atmosphere, the reducing gas is a mixed gas of hydrogen and inert gas, and the hydrogen content is 5%-15%.

[0008] Further, the covalently bonded non-porous polyarylene ether nitrile is synthesized by nucleophilic substitution reaction in a strong polar aprotic solvent with 4-nitrobenzonitrile, 4-difluorobenzophenone and resorcinol as raw materials, and anhydrous potassium carbonate as catalyst under nitrogen protection.

[0009] Further, the mass ratio of the oxygen vacancy regulated cobalt manganese oxide and the covalently bonded non-porous polyarylene ether nitrile in the composite system is 1:1-5:1.

[0010] Further, the covalent crosslinking is realized by adding a crosslinking agent, and the crosslinking agent is an organosilicon compound containing active functional groups.

[0011] A preparation method of an oxygen vacancy regulated cobalt manganese oxide-covalently bonded non-porous polyarylene ether nitrile composite system, comprising the following steps:

[0012] S1, a cobalt manganese precursor is prepared by co-precipitation method, and then is heat treated in a reducing gas atmosphere;

[0013] S2, covalently bonded non-porous polyarylene ether nitrile resin is synthesized by nucleophilic substitution reaction, and then a material with a specific morphology is prepared;

[0014] S3, after the oxygen vacancy regulated cobalt manganese oxide and the covalently bonded non-porous polyarylene ether nitrile material are physically mixed, a crosslinking agent is added to perform chemical crosslinking reaction.

[0015] Further, in the preparation of the oxygen vacancy regulated cobalt manganese oxide, the pH value of the solution in the co-precipitation method is adjusted to 8.5-9.5, the inert gas protection is used during the heat treatment, the temperature is raised to 350-450℃, and the temperature is maintained for 1-3 hours, and the treatment temperature in the reducing gas atmosphere is 350-450℃, and the treatment time is 0.5-2 hours.

[0016] Further, in the synthesis of the covalently bonded non-porous polyarylene ether nitrile, the reaction temperature is 170-190℃, and the reaction time is 8-14 hours.

[0017] Further, in the construction of the composite system, the crosslinking reaction temperature is 80-100℃, and the reaction time is 3-6 hours.

[0018] Further, the composite system is coated on a conductive substrate as an electrocatalyst to make a working electrode, which is applied to the process of hydrogen production by electrolysis of water in an 80-100℃ 6-8mol / L KOH solution as an electrolyte, and realizes efficient hydrogen evolution in a three-electrode system with a platinum sheet as a counter electrode and a saturated calomel electrode as a reference electrode. The hydrogen evolution overpotential of the composite system is not more than 120mV at a current density of 10mA / cm 2 , and the current density attenuation rate is less than 5% after 100 hours of continuous electrolysis at a current density of 10mA / cm 2 .

[0019] Compared with the prior art, the beneficial effects of the present application are:

[0020] 1. By precisely regulating the oxygen vacancies in cobalt-manganese oxides, the electrocatalytic activity is significantly improved, the hydrogen evolution overpotential is reduced, and the composite system exhibits excellent catalytic performance in high-temperature alkaline water electrolysis for hydrogen production, thereby improving the hydrogen evolution efficiency.

[0021] 2. Good stability: The introduction of covalently bonded non-porous polyarylether nitrile provides a stable support structure for cobalt-manganese oxides, enhances the stability of the composite system in a high-temperature alkaline environment, and prolongs the service life of the catalyst.

[0022] 3. The tight combination between cobalt-manganese oxides and covalently bonded non-porous polyarylether nitrile in the composite system through covalent cross-linking realizes the synergistic effect between the two, promotes the transfer of electrons and the effective utilization of active sites, and further improves the electrocatalytic performance.

[0023] 4. The raw materials used in the present application, such as cobalt salt, manganese salt, 4-nitrobenzonitrile, 4,4-difluorobenzophenone and resorcinol, are common chemical raw materials, widely available and relatively low in cost, which is conducive to large-scale industrial production. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be described below in a clear and complete manner. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0025] Example 1

[0026] First, the cobalt-manganese oxide with oxygen vacancy regulation is prepared

[0027] (1) 10.98 g of cobalt nitrate hexahydrate (Co(N03)2-6H20, molecular formula: CoN20e-6H20) and 5.09 g of manganese nitrate tetrahydrate (Mn(N03)2-4H20, molecular formula: MnN20e-4H20) were weighed and dissolved in 200 mL of deionized water to obtain a mixed solution. Under stirring, 2 mol / L sodium hydroxide solution (NaOH, molecular formula: NaOH) was slowly added dropwise to adjust the pH of the solution to 9.0, and cobalt-manganese hydroxide (molecular formula: Co x Mn y (OH) n ) precipitate was generated. After stirring for 1 hour, the precipitate was filtered, washed with deionized water until neutral, and dried at 80°C for 12 hours to obtain a cobalt-manganese precursor powder.

[0028] (2) The cobalt-manganese precursor powder was placed in a tube furnace and heated to 400°C at a heating rate of 5°C / min under argon (Ar) protection. Then, the furnace was switched to a mixed gas of hydrogen (H2) and argon (Ar) (hydrogen content of 10%) and continued to be treated at 400°C for 1 hour to generate oxygen vacancy regulated cobalt-manganese oxide (molecular formula: Co x Mn y O n-a , where a is the number of oxygen vacancies). Finally, it was cooled to room temperature in an argon atmosphere to obtain an oxygen vacancy regulated cobalt-manganese oxide powder.

[0029] Covalently bonded non-porous polyarylene ether nitrile was then synthesized

[0030] (1) In a three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, 4.64 g of 4-nitrobenzonitrile (molecular structure: a nitro group (-NO2) and a cyano group (-CN) are connected to the para position of a benzene ring, respectively), 5.96 g of 4,4'-difluorobenzophenone (molecular structure: two benzene rings are connected by a carbonyl group (-CO-), and each benzene ring has a fluorine atom (-F) connected to the para position), 2.28 g of resorcinol (molecular structure: two hydroxyl groups (-OH) are connected to the meta position of a benzene ring), 4.14 g of anhydrous potassium carbonate (molecular formula: K2CO3) and 100 mL of N,N-dimethylacetamide (molecular formula: C4H9NO) were added. Under nitrogen (N2) protection, it was heated to 180°C for 12 hours to synthesize covalently bonded non-porous polyarylene ether nitrile (repeating unit molecular structure: two benzene rings are connected by an ether bond (-O-) and a ketone group (-CO-), and one of the benzene rings is connected to a nitro-derived group and a cyano group (-CN)) through a nucleophilic substitution reaction. After the reaction was completed, the reaction solution was poured into 500 mL of deionized water, and white precipitate was precipitated. The precipitate was filtered, washed with deionized water three times, and dried at 120°C for 8 hours to obtain covalently bonded non-porous polyarylene ether nitrile resin.

[0031] (2) Covalently bonded non-porous poly(arylene ether nitrile) resin was dissolved in dichloromethane (molecular formula: CH2Cl2) to prepare a solution with a mass fraction of 10%. The solution was uniformly cast on a glass plate using a solution casting method, and the solvent was evaporated at room temperature. Then, the residual organic solvent was removed by heat treatment at 100°C for 2 hours to obtain a covalently bonded non-porous poly(arylene ether nitrile) film.

[0032] Finally, the composite system was constructed

[0033] (1) 0.5 g of oxygen vacancy regulated cobalt manganese oxide (Co x Mn y O n-a ) powder and 0.5 g of covalently bonded non-porous poly(arylene ether nitrile) ([C 26 H 15 N3O5] n ) film were weighed and cut into small pieces, then put into a marver mortar and ground thoroughly to obtain a physical mixture.

[0034] (2) 0.1 g of γ-aminopropyltriethoxysilane (molecular structure: one end is an amino group (-NH2) connected to three methylene groups (-CH2-), the other end is connected to a silicon atom, and the silicon atom is connected to three ethoxy groups (-OC2H5)) was added as a crosslinking agent to the physical mixture, and the mixture was stirred at 80°C for 3 hours to allow the crosslinking agent to covalently crosslink with the covalently bonded non-porous poly(arylene ether nitrile) and simultaneously anchor the cobalt manganese oxide firmly in the covalently bonded non-porous poly(arylene ether nitrile) structure to obtain a composite system.

[0035] Example 2

[0036] First, the preparation of oxygen vacancy regulated cobalt manganese oxide

[0037] (1) The ratio of cobalt salt and manganese salt was changed, and 8.23 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O, molecular formula: CoN2O6·6H2O) and 7.63 g of manganese nitrate tetrahydrate (Mn(NO3)2·4H2O, molecular formula: MnN2O6·4H2O) were weighed and co-precipitated according to the method in Example 1 to prepare cobalt manganese precursor (Co x Mn y (OH) n ) powder.

[0038] (2) When heat treatment was performed in a tube furnace, the content of hydrogen (H2) in the reducing gas was adjusted to 15%, and the other conditions were the same as in Example 1 to obtain oxygen vacancy regulated cobalt manganese oxide (Co x Mn y O n-a ) powder.

[0039] Then, covalently bonded non-porous poly(arylene ether nitrile) was synthesized and a composite system was constructed

[0040] (1) Covalent-bonded nonporous poly(arylene ether nitrile) ([C 26 H 15 N3O5] n ) fibers were prepared by electrospinning. The covalent-bonded nonporous poly(arylene ether nitrile) resin was dissolved in a mixed solvent of dichloromethane (CH2Cl2) and N,N-dimethylformamide (C3H7NO) (volume ratio of 3:1) to prepare a solution with a mass fraction of 15%. The solution was loaded into an electrospinning device with a syringe needle, and electrospinning was performed under the conditions of a voltage of 15 kV and a receiving distance of 15 cm to obtain covalent-bonded nonporous poly(arylene ether nitrile) fibers. The fibers were heat-treated at 150°C for 3 hours to remove residual solvent.

[0041] (2) 0.6 g of oxygen vacancy regulated cobalt manganese oxide (Co x Mn y O n-a ) powder and 0.4 g of covalent-bonded nonporous poly(arylene ether nitrile) ([C 26 H 15 N3O5] n ) fibers were weighed and uniformly mixed, then 0.12 g of γ-glycidoxypropyltrimethoxysilane (molecular structure: one end is a glycidyl ether group (containing an epoxy structure), connected to three methylene groups (-CH2-), the other end is connected to a silicon atom, and the silicon atom is connected to three methoxy groups (-OCH3)) was added as a crosslinking agent, and the mixture was stirred at 90°C for 4 hours to obtain a composite system.

[0042] Example 3

[0043] First, oxygen vacancy regulated cobalt manganese oxide was prepared

[0044] (1) 6.59 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O, molecular formula: CoN2O6·6H2O) and 10.18 g of manganese nitrate tetrahydrate (Mn(NO3)2·4H2O, molecular formula: MnN2O6·4H2O) were dissolved in 200 mL of deionized water and stirred uniformly to obtain a mixed solution. Under stirring conditions, 2 mol / L sodium hydroxide solution (NaOH) was slowly added dropwise, and the pH value of the solution was adjusted to 9.5 to produce cobalt manganese hydroxide (Co x Mn y (OH) n ) precipitate. After continuing to stir for 1.5 hours, the precipitate was filtered, washed with deionized water until neutral, and dried at 85°C for 10 hours to obtain a cobalt manganese precursor powder.

[0045] (2) The cobalt-manganese precursor powder was placed in a tube furnace and heated to 450°C at a rate of 6°C / min under argon (Ar) protection for 1.5 hours. Then the mixed gas of hydrogen (H2) and argon (Ar) (hydrogen content of 8%) was switched on and the treatment was continued at 450°C for 1.5 hours to generate oxygen vacancy regulated cobalt-manganese oxide (Co x Mn γ O n-a ). Finally, it was cooled to room temperature in an argon atmosphere to obtain oxygen vacancy regulated cobalt-manganese oxide powder.

[0046] Then the covalently bonded non-porous polyarylene ether nitrile

[0047] (1) In a three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, 5.8 g of 4-nitrobenzonitrile (molecular structure: nitro (-NO2) and cyano (-CN) are connected to the para position of the benzene ring, respectively), 7.45 g of 4,4'-difluorobenzophenone (molecular structure: two benzene rings are connected by a carbonyl (-CO-), and each benzene ring is connected to a fluorine atom (-F) at the para position), 2.85 g of resorcinol (molecular structure: two hydroxyl groups (-OH) are connected to the meta position of the benzene ring), 5.18 g of anhydrous potassium carbonate (K2CO3) and 120 mL of N,N-dimethylacetamide (C4H9NO) were added. Under nitrogen (N2) protection, it was heated to 190°C for 10 hours to synthesize covalently bonded non-porous polyarylene ether nitrile ([C 26 H 15 N3O5] n ). After the reaction was completed, the reaction solution was poured into 600 mL of deionized water, and white precipitate was precipitated. The precipitate was filtered, washed with deionized water 4 times, and dried at 130°C for 7 hours to obtain covalently bonded non-porous polyarylene ether nitrile resin.

[0048] (2) The covalently bonded non-porous polyarylene ether nitrile resin was dissolved in dichloromethane (CH2Cl2) to prepare a solution with a mass fraction of 12%. Electrospinning was carried out under the conditions of a voltage of 16 kV and a receiving distance of 16 cm to obtain covalently bonded non-porous polyarylene ether nitrile fibers. The fibers were heat treated at 160°C for 2.5 hours to remove residual solvents.

[0049] Finally, the composite system was constructed

[0050] (1) 0.7 g of oxygen vacancy regulated cobalt-manganese oxide (Co x Mn y O n-a ) powder and 0.3 g of covalently bonded non-porous polyarylene ether nitrile ([C 26 H 15 N3O5] n) fibers, which were mixed and then put into a ball mill to be ball-milled for 2 hours at a rotation speed of 300 r / min to obtain a physical mixture.

[0051] (2) 0.15 g of γ-glycidoxypropyltrimethoxysilane (molecular structure: glycidoxy group (containing an epoxy structure) at one end, three methylene groups (-CH2-) connected, silicon atom at the other end, and three methoxy groups (-OCH3) connected to the silicon atom) was added to the physical mixture as a crosslinking agent, and the mixture was stirred and reacted at 95°C for 5 hours to obtain a composite system.

[0052] Comparative Example 1

[0053] Preparation of cobalt-manganese oxide with no oxygen vacancy regulation

[0054] (1) Cobalt-manganese precursor (Co x Mn y (OH) n ) powder was obtained according to the preparation method of cobalt-manganese precursor in Example 1. The cobalt-manganese precursor powder was heated in a tube furnace to 400°C at a heating rate of 5°C / min under protection of argon (Ar) only, and kept for 4 hours without reduction gas treatment to obtain cobalt-manganese oxide with no oxygen vacancy regulation (molecular formula: Co x Mn y O n ) powder.

[0055] (2) Construction of composite system

[0056] The cobalt-manganese oxide with no oxygen vacancy regulation (Co X Mn y O n ) powder was compounded with the covalently bonded non-porous polyarylether nitrile ([C 26 H 15 N3O5] n ) film according to the method in Example 1 to obtain a composite system.

[0057] Comparative Example 2

[0058] Only the covalently bonded non-porous polyarylether nitrile was used as an electrode material, and the covalently bonded non-porous polyarylether nitrile ([C 26 H 15 N3O5] n ) film was directly used as a working electrode without being compounded with the cobalt-manganese oxide.

[0059] Comparative Example 3

[0060] Preparation of composite system without covalent crosslinking

[0061] (1) 0.5 g of cobalt-manganese oxide with oxygen vacancy regulation (Co x Mnγ O n-a ) powder (same as example 1) and 0.5 g covalently bonded non-porous polyarylene ether nitrile ([C 26 H 15 N3O5] n ) thin film (same as example 1), which was cut into pieces and put into a marver, and mixed well by grinding. No crosslinking agent was added, and a composite system without covalent crosslinking was obtained.

[0062] Performance test

[0063] The hydrogen production performance of the composite system in high-temperature alkaline electrolysis water was tested, and the results showed that the hydrogen evolution overpotential was 150 mV at a current density of 10 mA / cm 2 , and the current density decayed by about 15% after continuous electrolysis for 100 hours at a current density of 10 mA / cm 2 . Compared with example 1, the combination of cobalt-manganese oxide and covalently bonded non-porous polyarylene ether nitrile was not strong enough due to the absence of covalent crosslinking, resulting in a decrease in electrocatalytic performance and stability.

[0064] The performance data comparison table is as follows:

[0065]

[0066]

[0067] From the above examples, comparative examples, and performance data comparison table, it can be more clearly seen that the oxygen vacancy regulated cobalt-manganese oxide-covalently bonded non-porous polyarylene ether nitrile composite system prepared by the present application exhibits excellent electrocatalytic performance and stability under different preparation conditions, and the performance of the composite system can be significantly improved through covalent crosslinking and oxygen vacancy regulation.

[0068] The preferred embodiments of the present application disclosed above are only used to help explain the present application. The preferred embodiments do not describe all the details, nor limit the present application to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of the present application. The present application selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present application, so that those skilled in the art can well understand and utilize the present application. The present application is only subject to the claims and the entire scope and equivalents thereof.

Claims

1. An oxygen vacancy-regulated cobalt manganese oxide-covalently bonded non-porous poly (arylene ether nitrile) composite system, characterized in that: The invention comprises oxygen vacancy-regulated cobalt manganese oxide and covalently bonded non-porous polyarylethernitrile. The oxygen vacancy-regulated cobalt manganese oxide is anchored in the structure of the covalently bonded non-porous polyarylethernitrile through covalent cross-linking.

2. The oxygen vacancy-regulated cobalt manganese oxide-covalently bonded non-porous poly (arylene ether nitrile) composite system according to claim 1, characterized in that: The oxygen vacancy-controlled cobalt-manganese oxide is prepared by coprecipitating a cobalt-manganese precursor, and then subjected to heat treatment in a reducing gas atmosphere. The reducing gas is a mixed gas of hydrogen and inert gas, and the hydrogen content is 5%-15%.

3. The oxygen vacancy-regulated cobalt manganese oxide-covalently bonded non-porous poly (arylene ether nitrile) composite system according to claim 1, characterized in that: The covalently bonded non-porous polyarylether nitrile is synthesized by a nucleophilic substitution reaction using 4-nitrobenzonitrile, 4-difluorobenzophenone and resorcinol as raw materials in a strongly polar aprotic solvent with anhydrous potassium carbonate as a catalyst under nitrogen protection.

4. The oxygen vacancy-regulated cobalt manganese oxide-covalently bonded non-porous poly (arylene ether nitrile) composite system according to claim 1, characterized in that: The oxygen vacancies in the composite system regulate the mass ratio of the cobalt manganese oxide to the covalently bonded non-porous polyarylethernitrile to be 1:1-5:

1.

5. The oxygen vacancy-regulated cobalt manganese oxide-covalently bonded non-porous poly (arylene ether nitrile) composite system according to claim 1, characterized in that: The covalent crosslinking is achieved by adding a crosslinking agent, which is an organosilicon compound containing active functional groups.

6. A method for preparing an oxygen vacancy-regulated cobalt manganese oxide-covalently bonded non-porous poly (arylene ether nitrile) composite system, characterized in that: The following steps are involved: S1. preparing a cobalt-manganese precursor by a coprecipitation method, and then heat-treating it in a reducing gas atmosphere; S2, synthesizing a covalently bonded non-porous poly(arylene ether nitrile) resin by a nucleophilic substitution reaction, and then preparing a material with a specific morphology; S3. Physically mix the oxygen vacancy-controlled cobalt manganese oxide with the covalently bonded non-porous poly(arylene ether nitrile) material, and then add a cross-linking agent to carry out a chemical cross-linking reaction.

7. The preparation method according to claim 6, characterized in that When preparing oxygen vacancy-regulated cobalt manganese oxide, the pH value of the solution is adjusted to 8.5-9.5 in the coprecipitation method. During heat treatment, the temperature is raised to 350-450°C under inert gas protection and maintained for 1-3 hours. The treatment temperature in a reducing gas atmosphere is 350-450°C and the treatment time is 0.5-2 hours.

8. The preparation method according to claim 6, characterized in that When synthesizing the covalently bonded non-porous polyarylethernitrile, the reaction temperature is 170-190° C. and the reaction time is 8-14 hours.

9. The preparation method according to claim 6, characterized in that When constructing the composite system, the cross-linking reaction temperature is 80-100°C and the reaction time is 3-6 hours.

10. An application of the oxygen vacancy-regulated cobalt manganese oxide-covalently bonded non-porous poly(arylene ether nitrile) composite system according to any one of claims 1 to 5 in high-temperature alkaline water electrolysis for hydrogen production, characterized in that: The composite system is coated as an electrocatalyst on a conductive substrate to prepare a working electrode, which is applied to the process of hydrogen production by electrolysis of water using a 6-8 mol / L KOH solution at 80°C-100°C as an electrolyte, and achieves efficient hydrogen evolution in a three-electrode system, wherein the three-electrode system uses a platinum sheet as a counter electrode and a saturated calomel electrode as a reference electrode. The composite system has a current density of 10 mA / cm 2 The hydrogen evolution overpotential does not exceed 120mV, and at 10mA / cm 2 After continuous electrolysis for 100 hours at a current density of , the current density decay rate is less than 5%.

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