Carbon-coated iridium dioxide water electrolysis hydrogen production catalyst as well as preparation method and application thereof

Abstract

The invention relates to the technical field of catalysts for hydrogen production by electrolysis of water, in particular to a carbon-coated iridium dioxide catalyst for hydrogen production by electrolysis of water as well as a preparation method and application of the carbon-coated iridium dioxide catalyst for hydrogen production by electrolysis of water, the preparation method of the carbon-coated iridium dioxide catalyst for hydrogen production by electrolysis of water comprises the following steps: preparing carbon-coated iridium dioxide precursor powder from an iridium compound, a carboxyl carbon compound and an oxidizing agent; the preparation method comprises the following steps: carrying out a calcination oxidation reaction on a carbon-coated iridium dioxide aqueous electrolysis hydrogen production catalyst, immediately carrying out rapid cooling treatment after calcination is finished to prepare an initial catalyst, and carrying out washing, filtering and heating drying to prepare the carbon-coated iridium dioxide aqueous electrolysis hydrogen production catalyst. The prepared catalyst has excellent electrocatalytic activity and stability, the catalyst crystal has a microporous structure and a high specific surface area, the nanostructure with the high specific surface area is beneficial to further improvement of the catalytic activity, and the loading capacity of the catalyst to Ir is reduced while the catalytic activity is ensured, so that the cost is remarkably reduced. The catalyst has a good application prospect in water electrolysis hydrogen evolution and oxygen evolution reactions.

Description

Technical Field

[0001] The invention relates to the technical field of water electrolysis hydrogen production catalysts, and in particular to a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst and a preparation method and application thereof. Background Art

[0002] As a clean and efficient energy carrier and storage medium, hydrogen has received extensive attention from research institutions and industries. It is widely regarded as a promising alternative to fossil fuels in the future. At present, water electrolysis is an environmentally friendly, efficient and feasible method for hydrogen production. Proton exchange membrane (PEM) water electrolysis is a promising technology that can efficiently produce high-purity hydrogen. IrO2, as a commercial electrocatalyst for the anode oxygen evolution reaction (OER) of proton exchange membrane (PEM) water electrolyzer, can remain stable under strong acidic and high-intensity corrosion conditions, and has many advantages such as excellent thermal stability and high conductivity. It is an ideal electrocatalyst material.

[0003] However, the anode electrocatalyst with the best comprehensive performance is based on iridium dioxide, but there are still many problems to be solved. For example, the catalytic activity of iridium dioxide still needs to be further improved compared with ruthenium dioxide; the electrochemical stability of iridium dioxide is still relatively poor under high potential conditions; in addition, the reserves of iridium in the earth's crust are extremely low, resulting in the price of iridium dioxide is still very expensive.

[0004] At present, iridium dioxide materials have broad application prospects in many catalytic reactions, but their shortcomings such as poor catalytic activity, stability that needs to be further improved, and high prices have greatly limited their application. Summary of the invention

[0005] In order to overcome the shortcomings of the prior art, the first object of the present invention is to provide a method for preparing a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst. The electrocatalytic activity and stability of the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst prepared by the preparation method are significantly improved. At the same time, the loading amount of iridium dioxide is reduced while ensuring the improvement of catalytic activity, thereby significantly reducing costs.

[0006] In order to overcome the shortcomings of the prior art, the second purpose of the present invention is to provide a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst, which has the advantages of high catalytic activity, good stability and low cost.

[0007] The third object of the present invention is to provide a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst for use in water electrolysis hydrogen evolution and oxygen evolution reactions.

[0008] In order to achieve the first object of the above invention, the technical solution adopted by the present invention is as follows:

[0009] The present invention provides a method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen, comprising the following steps:

[0010] S1. Preparing a carbon-coated iridium dioxide precursor powder: adding an iridium compound, a carboxyl carbon compound and an oxidant to a solvent, mixing them, and heating them for reaction to obtain a carbon-coated iridium dioxide precursor powder;

[0011] S2, preparing an initial catalyst: calcining the carbon-coated iridium dioxide precursor powder, and cooling it in an ice water bath or liquid nitrogen to obtain an initial catalyst;

[0012] S3, preparing a finished catalyst: washing, filtering and heating and drying the initial catalyst to obtain the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst.

[0013] The invention discloses a method for preparing a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst. The method comprises the following steps: preparing a carbon-coated iridium dioxide precursor powder by using an iridium compound, a carboxyl carbon compound and an oxidant, and then performing a calcination oxidation reaction. After the calcination is completed, the powder is immediately subjected to a rapid cooling treatment to obtain an initial catalyst. The carbon-coated iridium dioxide electrolysis water hydrogen production catalyst is obtained after washing, filtering and heating and drying. Among them, during the calcination oxidation reaction of the carbon-coated iridium dioxide precursor powder, the metal precursor and the oxidant are fused in the air at a higher temperature, and the carboxyl carbon compound is chelated with Ir as a chelating agent and a structure-directing agent to assist in crystal orientation, so that the crystal plane of the obtained carbon-coated iridium dioxide electrolysis water hydrogen production catalyst grows anisotropically and has a lattice tensile strain effect, and can significantly improve the electrocatalytic activity and stability, and the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst crystal has a microporous structure and a high specific surface area. The nanostructure with a high specific surface area is conducive to further improving the catalytic activity, and while ensuring the catalytic activity, the loading amount of Ir is reduced, thereby significantly reducing the cost. In addition, two gases, nitrogen dioxide and oxygen, are formed during the calcination and fusion process, and nitrogen dioxide and oxygen are released from the reaction system as by-products. The only solid by-product is a compound formed after the oxidant reacts, which can be easily dissolved in water and separated.

[0014] Furthermore, in step S1, the iridium compound is one or a combination of two or more of chloroiridic acid, potassium chloroiridate or iridium chloride; wherein the iridium compound is used as a precursor of the catalytically active iridium dioxide, and chloroiridic acid, potassium chloroiridate or iridium chloride is selected as the precursor of the catalytically active iridium dioxide, which is conducive to heating reaction in a solvent to obtain carbon-coated iridium dioxide precursor powder. And / or

[0015] The carboxyl carbon compound is one or a combination of two or more of glycine hydrochloride, benzenetricarboxylic acid, benzoic acid or cysteine; wherein the carboxyl carbon compound acts as a chelating agent and a structure directing agent, which can chelate with Ir to form a stable structure on the one hand, and can assist in crystal orientation on the other hand, so that the crystal plane of the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst grows anisotropically and has a lattice tensile strain effect, and can significantly improve the electrocatalytic activity and stability, and make the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst crystal have a microporous structure and a high specific surface area, thereby having the advantages of good electrocatalytic activity and stability. And / or

[0016] The oxidant is one or a combination of sodium nitrate, potassium nitrate, sodium bromide or potassium bromide; wherein, sodium nitrate, potassium nitrate, sodium bromide or potassium bromide is selected as the oxidant. On the one hand, it has the advantage of good oxidation performance and can promote the oxidation reaction of the iridium compound to generate iridium dioxide during calcination. On the other hand, the solid byproduct generated after the selected oxidant reacts with the iridium compound is easily dissolved in water and separated. And / or

[0017] The solvent is one or a combination of deionized water, isopropanol or ethanol. Deionized water, isopropanol or ethanol is used as a solvent to dissolve the iridium compound, the carboxyl carbon compound and the oxidant, to facilitate the solvent thermal reaction, and has the advantage of low material cost.

[0018] Further, the molar ratio of the iridium compound to the carboxyl carbon compound is 1:(1-10); and / or

[0019] The molar ratio of the iridium compound to the oxidant is 1:(3-30); and / or

[0020] The mass volume ratio of the iridium compound to the solvent is 800 mg: (20-25) mL.

[0021] Furthermore, in step S1, the mixing is carried out by ultrasound and / or stirring for 0.5 h to 12 h. In the solvothermal reaction, the uniformity of carbon coating can be promoted by ultrasound and / or stirring.

[0022] Furthermore, in step S1, the heating reaction is carried out in an oven at 80°C-120°C for 2h-12h.

[0023] Furthermore, in step S2, the calcination is to place the carbon-coated iridium dioxide precursor powder in a crucible, then put it into a muffle furnace and heat it to 350°C-500°C, and keep it warm in an air atmosphere for 1.5h-2.5h; wherein, the carbon-coated iridium dioxide precursor powder undergoes an oxidation reaction and a chelating effect in the air atmosphere through calcination.

[0024] and / or

[0025] The heating rate of the muffle furnace is 1°C / min-10°C / min, which is conducive to the reaction and the formation of crystals with microporous structures.

[0026] Furthermore, in step S2, the product is placed in an ice-water bath or liquid nitrogen for rapid cooling for 1 h to 2 h. After the calcination is completed, the calcined product is placed in an ice-water bath or liquid nitrogen for cooling, so that the calcined product can be rapidly cooled, thereby retaining a portion of the carboxyl carbon and better complexing on the surface of the material to form a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst.

[0027] Furthermore, in step S3, the initial catalyst is washed 1-3 times with deionized water and filtered; and / or

[0028] In the step S3, the heating and drying is to place the washed and filtered initial catalyst in an oven at 60° C.-80° C. and dry it for 20 h-30 h.

[0029] In order to achieve the second purpose of the above invention, the technical solution adopted by the present invention is as follows:

[0030] The invention provides a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst, which is prepared by the above-mentioned method for preparing the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst.

[0031] In order to achieve the third purpose of the above invention, the technical solution adopted by the present invention is as follows:

[0032] The present invention provides an application of a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst, and the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared by the above-mentioned method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst is applied in hydrogen evolution and oxygen evolution reactions of water electrolysis.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) The present invention provides a method for preparing a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst, which comprises the following steps: using an iridium compound, a carboxyl carbon compound and an oxidant to prepare a carbon-coated iridium dioxide precursor powder, and then subjecting the powder to a calcination oxidation reaction. After the calcination is completed, the powder is immediately subjected to a rapid cooling treatment to obtain an initial catalyst, and then the initial catalyst is obtained after washing, filtering and heating and drying. Among them, during the calcination oxidation reaction of the carbon-coated iridium dioxide precursor powder, the metal precursor and the oxidant are fused in the air at a relatively high temperature, and the carboxyl carbon compound acts as a chelating agent and a structure directing agent to chelate with Ir to assist crystal orientation, so that the crystal plane of the obtained carbon-coated iridium dioxide electrolysis water hydrogen production catalyst grows anisotropically and has a lattice tensile strain effect, and can significantly improve the electrocatalytic activity and stability. The carbon-coated iridium dioxide electrolysis water hydrogen production catalyst crystal has a microporous structure and a high specific surface area. The nanostructure with a high specific surface area is conducive to further improving the catalytic activity, and while ensuring the catalytic activity, the loading amount of Ir is reduced, thereby significantly reducing the cost.

[0035] (2) A method for preparing a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst of the present invention comprises calcining a carbon-coated iridium dioxide precursor powder, and forming two gases, nitrogen dioxide and oxygen, during the calcination and fusion process, and releasing nitrogen dioxide and oxygen from the reaction system as by-products. The only solid by-product is a compound formed after the oxidant reacts, which can be easily dissolved in water and separated.

[0036] (3) The present invention provides a method for preparing a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst. After the carbon-coated iridium dioxide precursor powder is calcined, the calcined product is placed in an ice water bath or liquid nitrogen for cooling, so that the calcined product can be quickly cooled, thereby allowing a portion of the carboxyl carbon to be retained and better complexed on the surface of the material to form a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst.

[0037] (4) The method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst of the present invention has the characteristics of simple process, simple and convenient operation, low production cost, and can be suitable for large-scale production.

[0038] (5) The carbon-coated iridium dioxide catalyst for water electrolysis and hydrogen production of the present invention is a nanostructure with micropores and a particle size of about 10 nm. The nanostructure with a high specific surface area is conducive to further improving the catalytic activity and reducing the Ir loading while ensuring the catalytic activity, thereby having the advantage of low cost.

[0039] (6) Application of a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst of the present invention, the application of the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst in the electrolysis water hydrogen evolution and oxygen evolution reaction can significantly improve the electrocatalytic activity and stability, and because the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst is a nanostructure with a high specific surface area, it is conducive to further improving the catalytic activity, and while ensuring the catalytic activity, the loading amount of Ir is reduced, thereby significantly reducing the cost. Therefore, the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst prepared by the present invention has a good application prospect in the electrolysis water hydrogen evolution and oxygen evolution reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 This is a TEM and lattice fringe image of a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Example 1 of the present invention. Figure 1 In the figure, Figure a is a TEM image, and Figure b is a lattice fringe image.

[0042] Figure 2 This is a TEM and lattice fringe image of an iridium dioxide electrocatalyst prepared in Comparative Example 1 of the present invention. Figure 2 In the figure, Figure c is a TEM image, and Figure d is a lattice fringe image.

[0043] Figure 3 This is a SEM image of a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen prepared in Example 1 of the present invention.

[0044] Figure 4 This is a SEM image of a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Comparative Example 2.

[0045] Figure 5 This is an XED diagram of a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Examples 1 to 4 of the present invention.

[0046] Figure 6 This is the XRD diagram of a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Examples 1 and 5 to 7 of the present invention.

[0047] Figure 7 This is the XRD diagram of a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Examples 8 to 12 of the present invention.

[0048] Figure 8This is a test graph of the electrochemical performance of a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Examples 1 to 4 of the present invention.

[0049] Fig. 9 This is a test diagram of the electrochemical performance of a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Examples 1 and 5 to 7 of the present invention.

[0050] Fig.10 This is a test graph of the electrochemical performance of a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Examples 8 to 12 of the present invention.

[0051] Fig.11 It is a test graph of the electrochemical performance of the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Example 1, the iridium dioxide electrocatalyst prepared in Comparative Example 1, and commercial iridium dioxide.

[0052] Fig.12 It is a graph showing the electrochemical stability test results of the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Example 1, the iridium dioxide electrocatalyst prepared in Comparative Example 1, and commercial iridium dioxide.

[0053] Fig.13 It is a comparison chart of the electrochemical performance of the carbon-coated iridium dioxide water electrolysis hydrogen production catalysts prepared in Example 1 and Comparative Example 2.

[0054] Fig.14 It is the XPS spectra of the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst of Example 1 and the iridium dioxide electrocatalyst of Comparative Example 1.

[0055] Fig.15 This is the EDS energy spectrum of the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Example 1 of the present invention.

[0056] Fig.16 This is the EDS energy spectrum of the iridium dioxide electrocatalyst prepared in Comparative Example 1. DETAILED DESCRIPTION

[0057] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0058] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. In the present invention, the singular forms "a", "said" and "the" used in the embodiments and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0059] Among them, the OER mentioned in the present invention refers to the electrocatalyst oxygen evolution reaction.

[0060] In an embodiment of the present invention, a method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst comprises the following steps:

[0061] S1. Preparing a carbon-coated iridium dioxide precursor powder: adding an iridium compound, a carboxyl carbon compound and an oxidant to a solvent, mixing them, and heating them for reaction to obtain a carbon-coated iridium dioxide precursor powder;

[0062] S2, preparing an initial catalyst: calcining the carbon-coated iridium dioxide precursor powder, and cooling it in an ice water bath or liquid nitrogen to obtain an initial catalyst;

[0063] S3, preparing a finished catalyst: washing, filtering and heating and drying the initial catalyst to obtain the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst.

[0064] In some embodiments, in step S1, the iridium compound is one or a combination of two or more of chloroiridic acid, potassium chloroiridate or iridium chloride; and / or

[0065] The carboxyl carbon compound is one or a combination of two or more of glycine hydrochloride, trimesic acid, benzoic acid or cysteine; and / or

[0066] The oxidant is one or a combination of two of sodium nitrate, potassium nitrate, sodium bromide or potassium bromide; and / or

[0067] The solvent is deionized water, isopropanol or ethanol, or a combination of two thereof.

[0068] In some embodiments, the molar ratio of the iridium compound to the carboxyl carbon compound is 1:(1-10); and / or

[0069] The molar ratio of the iridium compound to the oxidant is 1:(3-30); and / or

[0070] The mass volume ratio of the iridium compound to the solvent is 800 mg: (20-25) mL.

[0071] In some embodiments, in step S1, the mixing is performed by ultrasound and / or stirring for 0.5 h to 12 h.

[0072] In some embodiments, in step S1, the heating reaction is carried out in an oven at 80°C-120°C for 2h-12h.

[0073] In some embodiments, in step S2, the calcination is to place the carbon-coated iridium dioxide precursor powder in a crucible, then place it in a muffle furnace and heat it to 350° C.-500° C., and keep it in an air atmosphere for 1.5 h-2.5 h; and / or

[0074] The heating rate of the muffle furnace is 1°C / min-10°C / min.

[0075] In some embodiments, in step S2, the device is placed in an ice water bath or liquid nitrogen for rapid cooling for 1 h to 2 h.

[0076] In some embodiments, in step S3, the initial catalyst is washed 1-3 times with deionized water and filtered; and / or

[0077] In the step S3, the heating and drying is to place the washed and filtered initial catalyst in an oven at 60° C.-80° C. and dry it for 20 h-30 h.

[0078] In an embodiment of the present invention, a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst is prepared by the above-mentioned method for preparing a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst.

[0079] In an embodiment of the present invention, an application of a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst is provided, and the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared by the above-mentioned method of preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst is used in the electrolysis of water hydrogen evolution and oxygen evolution reaction.

[0080] The following describes the invention in conjunction with specific embodiments.

[0081] Example 1

[0082] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen comprises the following steps:

[0083] S1. Preparation of carbon-coated iridium dioxide precursor powder: adding chloroiridic acid, glycine hydrochloride and sodium nitrate to isopropanol, mixing by ultrasonic oscillation for 0.5 h, and reacting in an oven at 120° C. for 12 h to obtain carbon-coated iridium dioxide precursor powder;

[0084] In this embodiment, the molar ratio of chloroiridic acid to glycine hydrochloride is 1:5; the molar ratio of chloroiridic acid to sodium nitrate is 1:5; and the mass volume ratio of chloroiridic acid to isopropanol is 800 mg:23 mL.

[0085] S2. Preparation of initial catalyst: placing carbon-coated iridium dioxide precursor powder in a crucible, then placing it in a muffle furnace and heating it to 450°C at a heating rate of 5°C / min for calcination, and keeping it in an air atmosphere for 2 hours, then placing the crucible in an ice water bath for rapid cooling for 1.5 hours to obtain an initial catalyst;

[0086] S3. Preparation of finished catalyst: The initial catalyst is washed once with deionized water, filtered, and then placed in an oven at 60° C. to dry for 24 hours to obtain a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst.

[0087] Example 2

[0088] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen, the difference between this embodiment and embodiment 1 is that the molar ratio of chloroiridic acid to glycine hydrochloride is 1:1. The rest of the preparation method is the same as that of embodiment 1.

[0089] Example 3

[0090] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen, the difference between this embodiment and embodiment 1 is that the molar ratio of chloroiridic acid to glycine hydrochloride is 1:3. The rest of the preparation method is the same as that of embodiment 1.

[0091] Example 4

[0092] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen, the difference between this embodiment and embodiment 1 is that the molar ratio of chloroiridic acid to glycine hydrochloride is 1:10. The rest of the preparation method is the same as that of embodiment 1.

[0093] Example 5

[0094] A method for preparing a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst, the difference between this embodiment and embodiment 1 is that: in step S2, the calcination temperature of the carbon-coated iridium dioxide precursor powder in the muffle furnace is 350° C. The rest of the preparation method is the same as that of embodiment 1.

[0095] Example 6

[0096] A method for preparing a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst, the difference between this embodiment and embodiment 1 is that: in step S2, the calcination temperature of the carbon-coated iridium dioxide precursor powder in the muffle furnace is 400° C. The rest of the preparation method is the same as embodiment 1.

[0097] Example 7

[0098] A method for preparing a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst, the difference between this embodiment and embodiment 1 is that: in step S2, the calcination temperature of the carbon-coated iridium dioxide precursor powder in the muffle furnace is 500° C. The rest of the preparation method is the same as embodiment 1.

[0099] Example 8

[0100] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen comprises the following steps:

[0101] S1. Preparing carbon-coated iridium dioxide precursor powder: adding chloroiridic acid, benzenetricarboxylic acid and potassium nitrate to ethanol, mixing by ultrasonic oscillation for 1 hour, and reacting in an oven at 100° C. for 10 hours to obtain carbon-coated iridium dioxide precursor powder;

[0102] In this embodiment, the molar ratio of chloroiridic acid to benzenetricarboxylic acid is 1:5; the molar ratio of chloroiridic acid to potassium nitrate is 1:6; and the mass volume ratio of chloroiridic acid to ethanol is 800 mg:22 mL.

[0103] S2. Preparation of initial catalyst: placing carbon-coated iridium dioxide precursor powder in a crucible, then placing it in a muffle furnace and heating it to 450°C at a heating rate of 5°C / min for calcination, and keeping it in an air atmosphere for 2 hours, then placing the crucible in an ice water bath for rapid cooling for 1 hour to obtain an initial catalyst;

[0104] S3. Preparation of finished catalyst: The initial catalyst is washed twice with deionized water, filtered, and then placed in an oven at 70° C. to dry for 25 hours to obtain a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst.

[0105] Example 9

[0106] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen, the difference between this embodiment and embodiment 8 is that the molar ratio of chloroiridic acid to benzenetricarboxylic acid is 1:1. The rest of the preparation method is the same as that of embodiment 8.

[0107] Example 10

[0108] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen, the difference between this embodiment and embodiment 8 is that the molar ratio of chloroiridic acid to benzenetricarboxylic acid is 1:3. The rest of the preparation method is the same as that of embodiment 8.

[0109] Embodiment 11

[0110] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen, the difference between this embodiment and embodiment 8 is that the molar ratio of chloroiridic acid to benzenetricarboxylic acid is 1:7. The rest of the preparation method is the same as that of embodiment 8.

[0111] Example 12

[0112] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen, the difference between this embodiment and embodiment 8 is that the molar ratio of chloroiridic acid to benzenetricarboxylic acid is 1:9. The rest of the preparation method is the same as that of embodiment 8.

[0113] Embodiment 13

[0114] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen comprises the following steps:

[0115] S1. Preparing carbon-coated iridium dioxide precursor powder: adding potassium chloroiridate, benzoic acid and sodium bromide into deionized water, stirring for 12 hours, and reacting in an oven at 80° C. for 8 hours to obtain carbon-coated iridium dioxide precursor powder;

[0116] In this embodiment, the molar ratio of potassium chloroiridate to benzoic acid is 1:1; the molar ratio of potassium chloroiridate to sodium bromide is 1:3; and the mass volume ratio of potassium chloroiridate to deionized water is 800 mg:20 mL.

[0117] S2. Preparation of initial catalyst: placing carbon-coated iridium dioxide precursor powder in a crucible, then placing it in a muffle furnace and heating it to 400° C. at a heating rate of 1° C. / min for calcination, and keeping it in an air atmosphere for 2.5 hours, then placing the crucible in liquid nitrogen for rapid cooling for 1 hour to obtain an initial catalyst;

[0118] S3. Prepare finished catalyst: wash the initial catalyst three times with deionized water, filter it, and then dry it in an oven at 80° C. for 20 hours to obtain a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst.

[0119] Embodiment 14

[0120] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen comprises the following steps:

[0121] S1. Preparing carbon-coated iridium dioxide precursor powder: adding iridium chloride, cysteine ​​and potassium bromide to isopropanol, stirring for 0.5 h, and reacting in an oven at 90° C. for 11 h to obtain carbon-coated iridium dioxide precursor powder;

[0122] In this embodiment, the molar ratio of iridium chloride to cysteine ​​is 1:4; the molar ratio of iridium chloride to potassium bromide is 1:30; and the mass volume ratio of iridium chloride to isopropanol is 800 mg:25 mL.

[0123] S2. Preparation of initial catalyst: placing carbon-coated iridium dioxide precursor powder in a crucible, then placing it in a muffle furnace and heating it to 500° C. at a heating rate of 10° C. / min for calcination, and keeping it in an air atmosphere for 1.5 hours, then placing the crucible in an ice water bath for rapid cooling for 2 hours to obtain an initial catalyst;

[0124] S3. Prepare finished catalyst: wash the initial catalyst twice with deionized water, filter it, and then dry it in an oven at 65° C. for 30 hours to obtain a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst.

[0125] Embodiment 15

[0126] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen comprises the following steps:

[0127] S1. Preparation of carbon-coated iridium dioxide precursor powder: adding chloroiridic acid, glycine hydrochloride, sodium nitrate and potassium nitrate to ethanol, mixing by ultrasonication for 12 hours, and reacting in an oven at 110° C. for 2 hours to obtain carbon-coated iridium dioxide precursor powder;

[0128] In this embodiment, the molar ratio of chloroiridic acid to glycine hydrochloride is 1:7; the molar ratio of chloroiridic acid to the oxidant is 1:20; and the mass volume ratio of chloroiridic acid to ethanol is 800 mg:24 mL.

[0129] S2. Preparation of initial catalyst: placing carbon-coated iridium dioxide precursor powder in a crucible, then placing it in a muffle furnace and heating it to 400° C. at a heating rate of 4° C. / min for calcination, and keeping it in an air atmosphere for 1.8 h, then placing the crucible in liquid nitrogen for rapid cooling for 1.3 h to obtain an initial catalyst;

[0130] S3. Prepare finished catalyst: wash the initial catalyst once with deionized water, filter it, and then dry it in an oven at 75° C. for 22 hours to obtain a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst.

[0131] Example 16

[0132] A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen comprises the following steps:

[0133] S1. Preparation of carbon-coated iridium dioxide precursor powder: adding chloroiridic acid, potassium chloroiridate, glycine hydrochloride, benzenetricarboxylic acid and sodium nitrate to isopropanol, stirring for 5 hours, and reacting in an oven at 95° C. for 6 hours to obtain carbon-coated iridium dioxide precursor powder;

[0134] In this embodiment, the molar ratio of the iridium compound to glycine hydrochloride is 1:10; the molar ratio of the iridium compound to sodium nitrate is 1:10; and the mass volume ratio of the iridium compound to isopropanol is 800 mg:23 mL.

[0135] S2. Preparation of initial catalyst: placing carbon-coated iridium dioxide precursor powder in a crucible, then placing it in a muffle furnace and heating it to 470°C at a heating rate of 8°C / min for calcination, and keeping it in an air atmosphere for 2.1 hours, then placing the crucible in an ice water bath for rapid cooling for 1.8 hours to obtain an initial catalyst;

[0136] S3. Prepare finished catalyst: wash the initial catalyst twice with deionized water, filter it, and then dry it in an oven at 73° C. for 26 hours to obtain a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst.

[0137] Embodiment 17

[0138] A carbon-coated iridium dioxide water electrolysis hydrogen production catalyst application, the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared by the preparation method of any one of the carbon-coated iridium dioxide water electrolysis hydrogen production catalysts of Examples 1 to 15 above is used in the electrolysis of water hydrogen evolution and oxygen evolution reaction.

[0139] Comparative Example 1

[0140] A method for preparing an iridium dioxide electrocatalyst, the difference between this comparative example and Example 1 is that in step S1, no glycine hydrochloride is added. The rest of the preparation method is the same as Example 1.

[0141] Comparative Example 2

[0142] A method for preparing a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst, the difference between this embodiment and embodiment 1 is that: in the step of preparing the initial catalyst S2: placing the carbon-coated iridium dioxide precursor powder in a crucible, and then placing it in a muffle furnace for calcination and heat preservation, the muffle furnace stops heating and naturally cools to room temperature and then takes out the crucible to obtain the initial catalyst. The rest of the preparation method is the same as that of embodiment 1.

[0143] (I) Morphological characterization by transmission electron microscopy

[0144] The carbon-coated iridium dioxide electrolysis catalyst for hydrogen production from water prepared in Example 1 and the iridium dioxide electrocatalyst prepared in Comparative Example 1 were characterized by transmission electron microscopy (TEM). The TEM and lattice fringe images of the carbon-coated iridium dioxide electrolysis catalyst for hydrogen production from water prepared in Example 1 are as follows: Figure 1 The TEM and lattice fringe images of an iridium dioxide electrocatalyst prepared in Comparative Example 1 are shown in Figure 2 shown.

[0145] Figure 1 In the figure, Figure a is a TEM image, and Figure b is a lattice fringe image. Figure 2 In the figure, Figure c is a TEM image, and Figure d is a lattice fringe image.

[0146] Depend on Figure 1 and Figure 2 By comparison, it can be seen that Figure 1 and Figure 2 TEM image of a carbon-coated iridium dioxide electrolysis water hydrogen production catalyst prepared in Example 1. Since glycine hydrochloride is added in step S1 to prepare the carbon-coated iridium dioxide precursor powder, the surface of the particles of the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst prepared is coated with a uniform carbon protective layer, and the particle size is significantly smaller before and after comparison, please refer to Figure 1 Figure a and Figure 2 Figure c in Figure 2. Figure 1 and Figure 2 In the lattice fringe diagram, it is also observed that the carbon-coated iridium dioxide catalyst for electrolysis of water to produce hydrogen in Example 1 exhibits selective growth of crystal faces (101 in the figure) and also undergoes lattice tensile strain, see Figure 2 Figure b and Figure 2 Figure d in .

[0147] (II) Morphological characterization by scanning electron microscopy

[0148] The carbon-coated iridium dioxide electrolysis water hydrogen production catalysts prepared in Example 1 and Comparative Example 2 were characterized by scanning electron microscopy (SEM) morphology. The SEM image of the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst prepared in Example 1 is as follows: Figure 3 The SEM image of the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Comparative Example 2 is shown in Figure 4 shown.

[0149] Depend on Figure 3 It can be seen that the particles of the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Example 1 are all spherical and evenly dispersed without clustering into lumps, so that the prepared carbon-coated iridium dioxide water electrolysis hydrogen production catalyst has a high specific surface area, which is conducive to further improving the catalytic activity.

[0150] Depend on Figure 4 It can be seen that in Comparative Example 2, since no rapid cooling was performed after calcination and heat preservation, most of the particles of the obtained carbon-coated iridium dioxide water electrolysis hydrogen production catalyst were agglomerated into blocks, and thus the specific surface area was low, resulting in poor electrocatalytic activity.

[0151] Therefore, in the present invention, in the initial catalyst preparation step S2, the carbon-coated iridium dioxide precursor powder is calcined and kept warm, and then placed in an ice water bath or liquid nitrogen for rapid cooling. The particles of the prepared carbon-coated iridium dioxide water electrolysis hydrogen production catalyst are all spherical and evenly distributed without clustering, and thus have a high specific surface area, thereby improving the electrocatalytic activity.

[0152] (III) X-ray diffraction analysis

[0153] The carbon-coated iridium dioxide electrolysis water hydrogen production catalysts prepared in Examples 1 to 4 were subjected to X-ray diffraction analysis (XRD), as shown in FIG. Figure 5 shown. Figure 5 , the curve marked “1:5” refers to Example 1, the curve marked “1:1” refers to Example 2, the curve marked “1:3” refers to Example 3, and the curve marked “1:10” refers to Example 4.

[0154] Depend on Figure 5 It can be seen that the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared by adding glycine hydrochloride with different molar ratios can be proved through XRD pattern analysis that glycine hydrochloride is successfully wrapped on the particle surface in a carbon-coated manner, causing a low-angle shift in the lattice.

[0155] The carbon-coated iridium dioxide electrolysis water hydrogen production catalysts prepared in Examples 1, 5 and 7 were subjected to X-ray diffraction analysis (XRD), as shown in FIG. Figure 6 shown. Figure 6 , the curve marked “450°C” refers to Example 1, the curve marked “350°C” refers to Example 5, the curve marked “400°C” refers to Example 6, and the curve marked “500°C” refers to Example 7.

[0156] Depend on Figure 6 It can be seen that when the initial catalyst is prepared in step S2, the crystallinity of the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst obtained under different calcination temperature conditions is different. This shows that when preparing the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst, the crystallinity of the obtained carbon-coated iridium dioxide electrolysis water hydrogen production catalyst can be significantly changed by adjusting different calcination temperatures.

[0157] The carbon-coated iridium dioxide electrolysis water hydrogen production catalysts prepared in Examples 8 to 12 were subjected to X-ray diffraction analysis (XRD), as shown in FIG. Figure 7 shown. Figure 7 , the curve marked “1:5” refers to Example 8, the curve marked “1:1” refers to Example 9, the curve marked “1:3” refers to Example 10, the curve marked “1:7” refers to Example 11, and the curve marked “1:9” refers to Example 12.

[0158] Depend on Figure 7 It can be seen that the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared by adding different molar contents of trimethylene glycol, the XRD diagram analysis shows that a carboxyl carbon peak appears at a diffraction angle of about 13 degrees, and with the increase of the amount of trimethylene glycol added, the peak intensity is first strong and then weak, reaching a peak value when the molar ratio of chloroiridic acid to trimethylene glycol is 1:5, and the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst of Example 8 has the best OER activity performance, indicating that carboxyl carbon does play an optimizing role in OER activity.

[0159] (IV) Electrochemical performance test

[0160] Among them, the method used for electrochemical performance testing is as follows:

[0161] (1) Preparation of working electrode: The catalyst powder (4 mg) was mixed with ultrapure water (500 μL), ethanol (500 μL) and Nafion solution (40 μL) to prepare a catalyst slurry, which was then drop-coated on a glassy carbon electrode (or carbon paper) to achieve a catalyst loading of 125 μg / L.

[0162] (2) Electrolyte preparation: Add 7 mL of high concentration perchloric acid to 1000 mL of ultrapure water and stir evenly until the temperature reaches room temperature to obtain a 0.1 M HClO4 electrolyte.

[0163] (3) Electrochemical test: Electrochemical performance and stability tests were carried out in a three-electrode battery system. In the three-electrode system, a graphite rod was used as a counter electrode, Ag / AgCl was used as a reference electrode, and the prepared catalyst was used as a working electrode in a 0.1M HClO4 electrolyte. The above system was connected to an electrochemical workstation to test its linear voltammetry (LSV) curve to test its electrochemical oxygen evolution performance. The electrochemical test was carried out in an oxygen-saturated 0.1M HClO4 electrolyte at 25°C. In order to ensure the reliability of the data, the OER activity test was repeated three times, and the average value of the three times was taken as the measured value. The potential was calibrated with a reversible hydrogen electrode for each measurement. The linear sweep voltammetry method was from 1.2V to 1.8V, with a scan rate of 5mVs -1 The stability was evaluated at 10 mA cm -1 Perform chronopotentiometry testing.

[0164] According to the electrochemical performance test method, the carbon-coated iridium dioxide electrolysis water hydrogen production catalysts prepared in Examples 1 to 4 were respectively subjected to electrochemical performance tests. The test results showed that Figure 8 As shown. Figure 8 It can be seen that the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared by adding different molar ratios of glycine hydrochloride has the best OER activity when the molar ratio of iridium compound to carboxyl carbon compound is 1:5.

[0165] The electrochemical performance of the carbon-coated iridium dioxide water electrolysis hydrogen production catalysts prepared in Examples 1, 5 and 7 was tested respectively. The test results showed that if Fig. 9 As shown. Fig. 9 It can be seen that when the initial catalyst is prepared in step S2, the OER activity of the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst obtained under different calcination temperature conditions is different. Among them, when the calcination temperature is 450°C, the obtained carbon-coated iridium dioxide electrolysis water hydrogen production catalyst has the best OER activity. It can be seen that in Example 1, when the molar ratio of chloroiridic acid to glycine hydrochloride is 1:5 and the calcination temperature is 450°C, the obtained carbon-coated iridium dioxide electrolysis water hydrogen production catalyst has the smallest overpotential.

[0166] The electrochemical performance of the carbon-coated iridium dioxide water electrolysis hydrogen production catalysts prepared in Examples 8 to 12 was tested respectively. The test results showed that if Fig.10 As shown. Fig.10 It can be seen that in Example 8, when the molar ratio of chloroiridic acid to benzenetricarboxylic acid is 1:5 and the calcination temperature is 450°C, the obtained carbon-coated iridium dioxide water electrolysis hydrogen production catalyst has the minimum overpotential.

[0167] Therefore, it can be seen from the above tests that when the molar ratio of the iridium compound to the carboxyl carbon compound is 1:5 and the calcination temperature is 450°C, the obtained carbon-coated iridium dioxide water electrolysis hydrogen production catalyst has the minimum overpotential.

[0168] (V) Electrochemical properties and electrochemical impedance test of Example 1, Comparative Example 1 and commercial iridium dioxide

[0169] The carbon-coated iridium dioxide electrolysis catalyst for hydrogen production from water prepared in Example 1, the iridium dioxide electrocatalyst prepared in Comparative Example 1, and commercial iridium dioxide purchased on the market were subjected to electrochemical performance tests. The electrochemical performance test results are shown in FIG. Fig.11 shown.

[0170] Depend on Fig.11 It can be seen that carboxyl carbon compounds (such as glycine hydrochloride) have a significant improvement in electrochemical performance. The carbon-coated iridium dioxide electrolysis hydrogen production catalyst prepared by coating iridium dioxide with carboxyl carbon compounds has a significant advantage in electrochemical performance compared with comparative example 1 and commercial iridium dioxide catalysts.

[0171] (VI) Electrochemical stability test

[0172] The carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Example 1, the iridium dioxide electrocatalyst prepared in Comparative Example 1, and commercial iridium dioxide purchased on the market were respectively subjected to electrochemical stability tests.

[0173] The above electrochemical performance test method was used to perform electrochemical tests on the carbon-coated iridium dioxide electrolysis hydrogen production catalyst prepared in Example 1, the iridium dioxide electrocatalyst prepared in Comparative Example 1, and commercial iridium dioxide purchased on the market for more than 90 hours. The test results are as follows: Fig.12 shown.

[0174] Depend on Fig.12 It can be seen that the electrochemical stability of the iridium dioxide electrocatalyst prepared in Comparative Example 1 and the commercial iridium dioxide purchased on the market is relatively poor, while the stability test of the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared by the present invention reaches more than 90 hours, which has excellent durability compared with Comparative Example 1 and commercial iridium dioxide.

[0175] (VII) Comparison of electrochemical performance of Example 1 and Comparative Example 2

[0176] The electrochemical performance of the carbon-coated iridium dioxide water electrolysis hydrogen production catalysts prepared in Example 1 and Comparative Example 2 was tested respectively. The test results are as follows: Fig.13 shown.

[0177] Depend on Fig.13 It can be seen that in Example 1, the carbon-coated iridium dioxide precursor powder is calcined and kept warm in the initial catalyst preparation step S2, and then placed in an ice water bath or liquid nitrogen for rapid cooling, which can improve the electrochemical performance of the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst, thereby making the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst The OER activity is better. However, since Comparative Example 2 is not rapidly cooled after calcination and heat preservation, the electrochemical performance of the prepared carbon-coated iridium dioxide electrolysis water hydrogen production catalyst is relatively poor compared to Example 1, and thus its OER activity is also poor.

[0178] (VIII) X-ray Photoelectron Spectroscopy Analysis

[0179] The carbon-coated iridium dioxide electrolysis catalyst for hydrogen production from water prepared in Example 1 and the iridium dioxide electrocatalyst prepared in Comparative Example 1 were subjected to X-ray photoelectron spectroscopy analysis (XPS C 1s), and the analysis results are as follows: Fig.14 shown.

[0180] Depend on Fig.14 It can be seen that an OC=O signal appears in the XPS C 1s spectrum of the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst prepared in Example 1, indicating that part of the carboxyl carbon is retained on the surface of the material under rapid cooling.

[0181] (IX) EDS spectrum analysis test

[0182] The carbon-coated iridium dioxide electrolysis water hydrogen production catalyst prepared in Example 1 and the iridium dioxide electrocatalyst prepared in Comparative Example 1 were subjected to EDS energy spectrum analysis, and EDS images of elements C (red), Ir (blue) and O (green) were obtained. The test results are as follows: Fig.15 and 16 The EDS spectrum analysis of the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst prepared in Example 1 is as follows: Fig.15 As shown, the EDS spectrum analysis of the iridium dioxide electrocatalyst prepared in Comparative Example 1 is as follows Fig.16 shown.

[0183] according to Fig.15 and Fig.16 According to EDS spectrum analysis, the element content distribution of the carbon-coated iridium dioxide electrolysis catalyst for hydrogen production by water electrolysis prepared in Example 1 and the iridium dioxide electrocatalyst prepared in Comparative Example 1 is shown in Table 1. In addition, the carbon-coated iridium dioxide electrolysis catalyst for hydrogen production by water electrolysis prepared in Example 1 was also subjected to element content distribution analysis after the electrochemical stability test for 90 hours, as shown in Table 1.

[0184] Table 1 Element content distribution of the carbon-coated iridium dioxide electrolysis catalyst for hydrogen production in Example 1 and the iridium dioxide electrocatalyst in Comparative Example 1

[0185]

[0186] As can be seen from Table 1, the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst prepared in Example 1 has a high carbon content of nearly 50% due to the carboxyl carbon attached to the surface of the material. When the carbon-coated iridium dioxide electrolysis water hydrogen production catalyst in Example 1 was subjected to an electrochemical stability test and reacted for 90 hours, it was still found that the carbon content was stable at a certain level, indicating that the carboxyl carbon can indeed exist stably during the OER process and can prevent excessive dissolution of Ir.

[0187] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for preparing a carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen, characterized in that: The following steps are involved: S1. Preparing a carbon-coated iridium dioxide precursor powder: adding an iridium compound, a carboxyl carbon compound and an oxidant to a solvent, mixing them, and heating them for reaction to obtain a carbon-coated iridium dioxide precursor powder; S2, preparing an initial catalyst: calcining the carbon-coated iridium dioxide precursor powder, and cooling it in an ice water bath or liquid nitrogen to obtain an initial catalyst; S3, preparing a finished catalyst: washing, filtering and heating and drying the initial catalyst to obtain the carbon-coated iridium dioxide water electrolysis hydrogen production catalyst.

2. The method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In step S1, the iridium compound is one or a combination of two or more of chloroiridic acid, potassium chloroiridate or iridium chloride; and / or The carboxyl carbon compound is one or a combination of two or more of glycine hydrochloride, trimesic acid, benzoic acid or cysteine; and / or The oxidant is one or a combination of two of sodium nitrate, potassium nitrate, sodium bromide or potassium bromide; and / or The solvent is deionized water, isopropanol or ethanol, or a combination of two thereof.

3. The method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst according to claim 1, characterized in that: The molar ratio of the iridium compound to the carboxyl carbon compound is 1:(1-10); and / or The molar ratio of the iridium compound to the oxidant is 1:(3-30); and / or The mass volume ratio of the iridium compound to the solvent is 800 mg: (20-25) mL.

4. The method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In the step S1, the mixing is performed by ultrasound and / or stirring for 0.5 h to 12 h.

5. The method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In the step S1, the heating reaction is carried out in an oven at 80°C-120°C for 2h-12h.

6. The method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In the step S2, the calcination is to place the carbon-coated iridium dioxide precursor powder in a crucible, then put it into a muffle furnace, heat it to 350° C.-500° C., and keep it warm in an air atmosphere for 1.5 h-2.5 h; and / or The heating rate of the muffle furnace is 1°C / min-10°C / min.

7. The method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In step S2, the mixture is placed in an ice water bath or liquid nitrogen for rapid cooling for 1 h to 2 h.

8. The method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In the step S3, the initial catalyst is washed 1-3 times with deionized water and filtered; and / or In the step S3, the heating and drying is to place the washed and filtered initial catalyst in an oven at 60° C.-80° C. and dry it for 20 h-30 h.

9. A carbon-coated iridium dioxide catalyst for electrolyzing water to produce hydrogen, characterized in that: The catalyst is prepared by the method for preparing a carbon-coated iridium dioxide water electrolysis hydrogen production catalyst as described in any one of claims 1 to 8.

10. An application of a carbon-coated iridium dioxide catalyst for water electrolysis to produce hydrogen, characterized in that: Application of the carbon-coated iridium dioxide electrolysis hydrogen production catalyst prepared by the method for preparing a carbon-coated iridium dioxide electrolysis hydrogen production catalyst as described in any one of claims 1 to 8 in hydrogen evolution and oxygen evolution reactions by electrolysis of water.

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