Mixed molten salt method for rapidly preparing short-range ordered iridium oxide for PEM electrolyzed water

Abstract

The invention discloses a mixed molten salt method for rapidly preparing short-range ordered iridium oxide for PEM electrolyzed water, and belongs to the technical field of preparation of catalytic materials. According to the method, the short-range ordered iridium oxide can be prepared within 20 minutes to 2 hours. High-melting-point mixed molten salt is introduced as a reaction medium, so that iridium salt is uniformly dispersed, agglomeration is effectively reduced, and the preparation efficiency is improved; a morphology control template is not needed, the process is simplified, and the cost is reduced; by adjusting reaction parameters, the morphology and size of iridium oxide can be flexibly regulated and controlled, the particle size of a single nano crystal grain is 1.7-2.7 nm, and a short-range ordered structure is formed. The short-range ordered iridium oxide provides more active sites, enhances the structural stability, is good in dispersity, can be directly used as catalyst slurry, and realizes high catalytic activity under extremely low loading capacity; when the composite material is applied to a proton exchange membrane water electrolysis hydrogen production anode catalytic material, the catalyst cost is reduced, the energy conversion efficiency is improved, an electrolytic cell reaches high current density under low voltage, the performance is stable, and green hydrogen economic development is promoted.

Description

Technical Field

[0001] The invention belongs to the technical field of catalytic material preparation, and in particular relates to a mixed molten salt method for rapidly preparing short-range ordered iridium oxide for PEM water electrolysis. Background Art

[0002] Proton exchange membrane (PEM) water electrolysis hydrogen production technology is an efficient and environmentally friendly hydrogen production method. It uses proton exchange membrane as an electrolyte to produce hydrogen and oxygen by electrolyzing water. It has broad application prospects in renewable energy hydrogen production, energy storage, transportation and other fields. In proton exchange membrane (PEM) water electrolysis hydrogen production technology, the efficiency and stability of PEM water electrolysis hydrogen production technology largely depend on the anode catalyst material of the electrolyzer. The anode catalyst material needs to have excellent catalytic activity, excellent stability and good conductivity to effectively reduce electrolysis energy consumption and increase hydrogen yield. Rutile iridium dioxide (IrO2) is a currently commercialized acidic oxygen evolution catalyst. Although it meets the needs of PEM water electrolysis for hydrogen production to a certain extent, its preparation methods, such as chemical vapor deposition (CVD), sol-gel method and hydrothermal synthesis, have problems such as long preparation cycle, high energy consumption and low product order, which limit its application in industrial production. Although IrO2 obtained by the existing preparation method has certain catalytic activity, its performance is still not ideal and it is difficult to meet the growing demand for energy conversion efficiency. Therefore, the development of new and efficient iridium oxide preparation methods and the exploration of anode catalytic materials with better performance have become important directions for the current research on PEM water electrolysis for hydrogen production technology.

[0003] In order to improve the catalytic activity, researchers have developed many new iridium-based oxide catalysts, including layered iridium-based oxides, amorphous iridium oxides (IrOx) and composite metal oxides. These new catalysts show higher intrinsic activity than IrO2 under laboratory conditions, bringing new hope to PEM water electrolysis hydrogen production technology. However, despite the excellent performance of new iridium-based oxide catalysts under laboratory conditions, they still face many challenges in practical applications. In the acidic oxygen evolution process, iridium ions in iridium-based oxide catalysts are prone to desolvation, resulting in the destruction of the catalyst structure and the decline of performance; in the long-term operation process, its structure is prone to change, resulting in a rapid decline in catalytic activity. This instability limits the commercial application of the catalyst; although iridium oxide itself has a certain conductivity, some iridium-based oxide catalysts have poor conductivity, which affects the transmission efficiency of electrons on the catalyst surface, thereby reducing the catalytic reaction rate and failing to meet the needs of efficient water electrolysis hydrogen production. These problems seriously limit the widespread application of iridium-based oxide catalysts in PEM water electrolysis hydrogen production technology. Summary of the invention

[0004] In view of the low preparation efficiency of existing iridium-based oxide catalysts and the general problems of insufficient stability and high oxidation overpotential of iridium-based oxides in the acidic oxygen evolution reaction (OER) process, the purpose of the present invention is to provide a mixed molten salt method for rapidly preparing short-range ordered iridium oxide for PEM water electrolysis, and to rapidly prepare short-range ordered iridium oxide by the mixed molten salt method.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method, comprising: Step 1: adding an iridium source precursor to a molten composite salt and mixing the mixture, followed by cooling to obtain solid particles; The molten composite salt is a molten composite salt of sodium carbonate and sodium nitrate; Step 2: washing the solid particles obtained in step 1, and drying them to obtain short-range ordered iridium oxide; The particle size of the short-range ordered iridium oxide particles is 1.7 nm to 2.7 nm.

[0006] The molten composite salt is obtained by mixing and calcining sodium carbonate and sodium nitrate, and the mass ratio of the sodium carbonate to the sodium nitrate is 1:1-49.

[0007] Furthermore, the mass ratio of the sodium carbonate to the sodium nitrate is 1:24-49.

[0008] The calcination temperature is 360°C to 500°C, and the calcination time is 20 min to 2 h.

[0009] Furthermore, the calcination temperature is 360°C to 450°C, and the calcination time is 20 min to 1 h.

[0010] The iridium source precursor is any one of iridium trichloride hydrate, iridium trichloride and iridium dioxide.

[0011] Furthermore, the iridium source precursor is iridium trichloride hydrate.

[0012] The mass ratio of the iridium source precursor to the molten composite salt is 1:100-150.

[0013] Furthermore, the mass ratio of the iridium source precursor to the molten composite salt is 1:125.

[0014] In step 2, the drying is vacuum drying at 50°C to 100°C.

[0015] The short-range ordered iridium oxide obtained by the above method.

[0016] The above-mentioned short-range ordered iridium oxide is used in the preparation of anode catalytic materials for proton exchange membrane water electrolysis to produce hydrogen.

[0017] The present invention provides a proton exchange membrane water electrolysis hydrogen production anode, comprising an anode carrier and an anode catalytic material loaded thereon, wherein the anode catalytic material is the above-mentioned short-range ordered iridium oxide.

[0018] The invention provides a method for producing hydrogen by electrolyzing water using a proton exchange membrane, which adopts the above-mentioned proton exchange membrane electrolyzing water to produce hydrogen anode, adopts 0.1M HClO4 solution as electrolyte, and adopts a platinum mesh and an Ag / AgCl electrode as a counter electrode and a reference electrode respectively.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The invention provides a method for quickly preparing short-range ordered iridium oxide by a mixed molten salt method. The method introduces a high-melting-point molten composite salt as a reaction medium to promote uniform dispersion of an iridium source in a reaction system, thereby effectively reducing agglomeration of the generated iridium oxide, making the product more uniform and delicate. The whole process only takes 20 min to 2 h to form a short-range ordered structure, which significantly improves the preparation efficiency and greatly reduces the preparation difficulty. The method does not require the use of a morphology control template, simplifies the preparation process, reduces the production cost, and can flexibly control the morphology and size of the iridium oxide by adjusting the reaction temperature, time, and the amount of molten salt, thereby meeting the specific requirements of iridium oxide particles in different application scenarios. The obtained short-range ordered iridium oxide particles have a particle size of 1.7 to 2.7 nm, form a short-range ordered structure, and are conducive to improving their catalytic activity. The short-range ordered iridium oxide has excellent catalytic activity, stability, and electrical conductivity, so that it has broad application prospects in catalytic fields such as proton exchange membrane water electrolysis for hydrogen production.

[0020] The short-range ordered iridium oxide obtained by the preparation method of the present invention has a short-range ordered structure that is conducive to the transmission of electrons and the exposure of catalytic active sites. Compared with conventional disordered or low-order iridium oxide, the short-range ordered structure can provide more effective catalytic active sites, thereby improving the catalytic activity; in the acidic oxygen evolution process, the ordered crystal structure can better resist the desolvation of iridium ions, reduce the damage to the catalyst structure, thereby extending the service life of the catalyst and enhancing the structural stability of the catalyst; in the environment of PEM water electrolysis for hydrogen production, the short-range ordered iridium oxide has stronger corrosion resistance, reducing the performance degradation of the catalyst caused by corrosion; the particle size range of the short-range ordered iridium oxide nanoparticles of the present invention is 1.7-2.7 nm, the dispersibility is good, and it can be directly used as a catalyst slurry for catalytic reaction. Compared with ordinary block catalysts, it can achieve high catalytic activity under extremely low loading conditions; it has good catalytic activity and stability, and the catalyst has a high catalytic activity at 10 mA cm -2It exhibits a low overpotential of only 186 ~204 mV under current density and shows excellent stability in 590 ~ 600 hours of durability test, which has great potential for commercial application.

[0021] The application of the short-range ordered iridium oxide provided by the present invention in the preparation of anode catalytic materials for proton exchange membrane water electrolysis to produce hydrogen reduces the use cost of the catalyst, improves the energy conversion efficiency, and promotes the commercialization process of the technology; the proton exchange membrane electrolyzer using short-range ordered iridium oxide as the anode catalyst can achieve a higher current density (at 10 mA cm -2 It exhibits a low overpotential of 186 ~204 mV under current density, and there is no obvious performance degradation after 590 to 600 hours of operation. This excellent catalytic performance makes proton exchange membrane water electrolysis hydrogen production technology more competitive and helps promote the development of the green hydrogen economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is an X-ray diffraction (XRD) diagram of the short-range ordered iridium oxide of the present invention; Figure 2 The microscopic morphology of the short-range ordered iridium oxide of the present invention, wherein (a) is a scanning electron microscope image, and (b) is a transmission electron microscope image; Figure 3 The OER polarization curve and stability curve of the short-range ordered iridium oxide in 0.1M HClO4 solution of the present invention, where (a) is the OER polarization curve and (b) is the stability curve at a constant 10 mA cm -2 Stability curves at current density of . DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0024] Definition explanation: Overpotential: An important indicator to measure the oxygen evolution reaction activity of a catalyst. The lower the overpotential, the higher the oxygen evolution reaction activity of the catalyst.

[0025] Example 1 This embodiment provides a method for quickly preparing short-range ordered iridium oxide by a mixed molten salt method, which specifically includes the following steps: (1) Preparation of molten composite salt Weigh 0.1 g of sodium carbonate and 4.9 g of sodium nitrate solid, mix them evenly and place them in a muffle furnace at 360 °C. The heating program of the muffle furnace is: heating rate of 20 °C / min, and keeping warm for 20 min to obtain a uniform molten composite salt.

[0026] (2) Preparation of short-range ordered iridium oxide Weigh 40 mg of IrCl3·H2O and add it to the molten composite salt obtained in step (1), continue heating for 5 min, and then cool naturally to room temperature; the product is washed with deionized water, filtered, and dried in vacuo at 80°C to obtain 30 mg of short-range ordered iridium oxide.

[0027] The short-range ordered iridium oxide prepared in this example was tested for relevant properties: The crystal structure of the short-range ordered iridium oxide sample of this embodiment was characterized by X-ray diffraction (XRD), see the attached Figure 1 As shown, there are two broad XRD peaks located at about 34.4° and 59.9°, indicating that the iridium oxide (IrOx) in the sample prepared in this embodiment presents a structure similar to an amorphous state, which means that atoms or molecules have a certain arrangement order within a short distance, but lack a regular periodic arrangement over a long distance. Therefore, it can be inferred that the iridium oxide sample in this embodiment has a short-range ordered crystal structure.

[0028] Further investigation of the microstructure of the short-range ordered iridium oxide sample of this embodiment is shown in the attached Figure 2 As shown. Scanning electron microscope (SEM) images show that the surface of the short-range ordered iridium oxide sample of this embodiment is composed of stacked nanoparticles; transmission electron microscope (TEM) images further reveal the internal structure of the short-range ordered iridium oxide sample. The short-range ordered iridium oxide sample is composed of a large number of short-range ordered grains, and the size of a single grain is about 1.7~2.3 nm. The particle size after stacking is 65~175nm. There are a large number of grain boundaries (edge ​​sites) between the grains. Due to the presence of a large number of grain boundaries between the grains and the short-range order of the grains themselves, a highly disordered structure is presented as a whole, which is conducive to material transport and energy conversion in catalytic reactions.

[0029] Oxygen evolution evaluation under acidic conditions: Weigh 5 mg of short-range ordered iridium oxide nanoparticle solid powder and disperse it in 950 μL of ethanol aqueous solution (the volume ratio of water to ethanol is 1:1); then add 50 μL of perfluorosulfonic acid polymer solution (Nafion solution) and disperse it evenly in an ultrasonic machine to obtain a dispersion; measure 4 μL of the dispersion and drop it on a glassy carbon electrode (area 0.071 cm 2) and used it as the working electrode after drying. The reference electrode and the counter electrode were saturated silver chloride electrode and platinum wire, respectively. The electrolyte was 0.1M HClO4 solution. A three-electrode system was built and a three-electrode test was performed on an electrochemical workstation (Chenhua 760E). The potential obtained with the saturated silver chloride electrode as the reference electrode was converted into the reversible hydrogen electrode potential (RHE) in the performance diagram. RHE The performance curve is drawn by taking the horizontal axis and the corresponding current density or other performance index as the vertical axis. The constant current density is set to 10 mA cm on the electrochemical workstation. -2 The short-range ordered iridium oxide of this embodiment was subjected to a long-term catalytic stability test, and the voltage change of the working electrode was continuously recorded to evaluate the stability of the catalyst. For details, see the attached Figure 3 shown.

[0030] By the attached Figure 3 The data show that at 10 mA cm -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is only 186 mV, indicating that it has excellent oxygen evolution reaction activity; after 600 h of constant current density test, the voltage of the short-range ordered iridium oxide in this embodiment has no obvious increase, indicating that during the long-term catalytic reaction process, the activity of the short-range ordered iridium oxide has not significantly decayed. It can be seen that the short-range ordered iridium oxide prepared by the present invention has excellent catalytic stability.

[0031] Example 2 This embodiment provides a method for quickly preparing short-range ordered iridium oxide by a mixed molten salt method, which specifically includes the following steps: (1) Preparation of molten composite salt Weigh 0.1 g of sodium carbonate and 4.9 g of sodium nitrate solid, mix them evenly and place them in a muffle furnace at 500 °C. The heating program of the muffle furnace is: heating rate of 20 °C / min, keeping warm for 20 min, to obtain a uniform molten composite salt.

[0032] (2) Preparation of short-range ordered iridium oxide Weigh 40 mg of IrCl3·H2O and add it to the molten composite salt obtained in step (1), continue heating for 5 min, and then cool naturally to room temperature; the product is washed with deionized water, filtered, and dried in vacuo at 80 °C to obtain 30 mg of short-range ordered iridium oxide.

[0033] The particle size of a single nanocrystal is about 1.8~2.6 nm, and the particle size after accumulation is 70~181nm. -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is 200 mV, and it works stably for 596 h.

[0034] Example 3 This embodiment provides a method for quickly preparing short-range ordered iridium oxide by a mixed molten salt method, which specifically includes the following steps: (1) Preparation of molten composite salt Weigh 0.2 g of sodium carbonate and 4.8 g of sodium nitrate solid, mix them evenly and place them in a muffle furnace at 450 °C. The heating program of the muffle furnace is: heating rate of 20 °C / min, keeping warm for 60 min, to obtain a uniform molten composite salt.

[0035] (2) Preparation of short-range ordered iridium oxide Weigh 50 mg of iridium dioxide and add it to the molten composite salt obtained in step (1). Continue heating for 5 min and then cool naturally to room temperature. Wash the product with deionized water, filter it, and dry it in vacuum at 100 °C to obtain 30 mg of short-range ordered iridium oxide.

[0036] The particle size of a single nanocrystal is about 1.8~2.5nm, and the particle size after accumulation is 68~180nm. -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is 188 mV, and it works stably for 597 h.

[0037] Example 4 This embodiment provides a method for quickly preparing short-range ordered iridium oxide by a mixed molten salt method, which specifically includes the following steps: (1) Preparation of molten composite salt Weigh 0.1 g of sodium carbonate and 4.9 g of sodium nitrate solid, mix them evenly and place them in a muffle furnace at 450 °C. The heating program of the muffle furnace is: heating rate of 20 °C / min, keeping warm for 60 min, to obtain a uniform molten composite salt.

[0038] (2) Preparation of short-range ordered iridium oxide Weigh 50 mg of iridium dioxide and add it to the molten composite salt obtained in step (1). Continue heating for 5 min and then cool naturally to room temperature. Wash the product with deionized water, filter it, and dry it in vacuum at 100 °C to obtain 30 mg of short-range ordered iridium oxide.

[0039] The particle size of a single nanocrystal is about 1.8~2.4nm, and the particle size after accumulation is 66~179nm. -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is 189 mV, and it works stably for 598 hours.

[0040] Example 5 This embodiment provides a method for quickly preparing short-range ordered iridium oxide by a mixed molten salt method, which specifically includes the following steps: (1) Preparation of molten composite salt Weigh 2.5 g of sodium carbonate and 2.5 g of sodium nitrate solids, mix them evenly and place them in a muffle furnace at 360 °C. The muffle furnace heating program is: heating rate of 20 °C / min, heat preservation for 20 min, to obtain a uniform molten composite salt.

[0041] (2) Preparation of short-range ordered iridium oxide Weigh 40 mg of IrCl3·H2O and add it to the molten composite salt obtained in step (1), continue heating for 5 min, and then cool naturally to room temperature; the product is washed with deionized water, filtered, and vacuum dried to obtain 30 mg of short-range ordered iridium oxide.

[0042] The particle size of a single short-range ordered iridium oxide nanocrystal is about 1.7-2.4 nm, and the particle size after accumulation is 65-176 nm. -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is 187 mV, and it works stably for 599 hours.

[0043] Example 6 This embodiment provides a method for quickly preparing short-range ordered iridium oxide by a mixed molten salt method, which specifically includes the following steps: (1) Preparation of molten composite salt Weigh 2.5 g of sodium carbonate and 2.5 g of sodium nitrate solid, mix them evenly and place them in a muffle furnace at 500 °C. The heating program of the muffle furnace is: heating rate of 20 °C / min, keeping warm for 20 min, to obtain a uniform molten composite salt.

[0044] (2) Preparation of short-range ordered iridium oxide Weigh 40 mg of IrCl3·H2O and add it to the molten composite salt obtained in step (1), continue heating for 5 min, and then cool naturally to room temperature; the product is washed with deionized water, filtered, and vacuum dried to obtain 30 mg of short-range ordered iridium oxide.

[0045] The particle size of a single short-range ordered iridium oxide nanocrystal is about 1.8-2.7 nm, and the particle size after accumulation is 71-181 nm. -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is 201 mV, and it works stably for 595 h.

[0046] Comparative Example 1 A method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method is provided, which specifically comprises the following steps: (1) Preparation of molten composite salt Weigh 0.1 g of sodium chloride and 4.9 g of sodium nitrate solid, mix them evenly and place them in a muffle furnace at 360 °C. The heating program of the muffle furnace is: heating rate of 20 °C / min, and heat preservation for 20 min to obtain a uniform molten composite salt.

[0047] (2) Preparation of short-range ordered iridium oxide Weigh 40 mg of IrCl3·H2O and add it to the molten composite salt obtained in step (1), continue heating for 5 min, and then cool naturally to room temperature; the product is washed with deionized water, filtered, and dried in vacuo at 80°C to obtain 30 mg of short-range ordered iridium oxide.

[0048] The particle size of a single nanocrystal is about 2.5 nm, and the particle size after accumulation is 146~308nm. -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is 270 mV, and it works stably for 400 h.

[0049] Comparative Example 2 A method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method is provided, which specifically comprises the following steps: (1) Preparation of molten composite salt Weigh 0.1 g of sodium chloride and 4.9 g of sodium nitrate solid, mix them evenly and place them in a muffle furnace at 500 °C. The heating program of the muffle furnace is: heating rate of 20 °C / min, and keeping warm for 20 min to obtain a uniform molten composite salt.

[0050] (2) Preparation of short-range ordered iridium oxide Weigh 40 mg of IrCl3·H2O and add it to the molten composite salt obtained in step (1), continue heating for 5 min, and then cool naturally to room temperature; the product is washed with deionized water, filtered, and vacuum dried to obtain 30 mg of short-range ordered iridium oxide.

[0051] The particle size of a single nanocrystal is about 2.5 nm, and the particle size after accumulation ranges from 93 to 282 nm. -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is 306 mV, and it works stably for 383 h.

[0052] Comparative Example 3 A method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method is provided, which specifically comprises the following steps: (1) Preparation of molten composite salt Weigh 2.5 g of sodium chloride and 2.5 g of sodium nitrate solid, mix them evenly and place them in a muffle furnace at 360 °C. The heating program of the muffle furnace is: heating rate of 20 °C / min, and heat preservation for 20 min to obtain a uniform molten composite salt.

[0053] (2) Preparation of short-range ordered iridium oxide Weigh 40 mg of IrCl3·H2O and add it to the molten composite salt obtained in step (1), continue heating for 5 min, and then cool naturally to room temperature; the product is washed with deionized water, filtered, and vacuum dried to obtain 30 mg of short-range ordered iridium oxide.

[0054] The particle size of a single nanocrystal is about 2.5 nm, and the particle size after accumulation is 146~308nm. -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is 287 mV, and it works stably for 392 hours.

[0055] Comparative Example 4 A method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method is provided, which specifically comprises the following steps: (1) Preparation of molten composite salt Weigh 2.5 g of sodium chloride and 2.5 g of sodium nitrate solid, mix them evenly and place them in a muffle furnace at 500 °C. The muffle furnace heating program is: heating rate of 20 °C / min, heat preservation for 20 min, to obtain a uniform molten composite salt.

[0056] (2) Preparation of short-range ordered iridium oxide Weigh 40 mg of IrCl3·H2O and add it to the molten composite salt obtained in step (1), continue heating for 5 min, and then cool naturally to room temperature; the product is washed with deionized water, filtered, and vacuum dried to obtain 30 mg of short-range ordered iridium oxide.

[0057] The particle size of a single nanocrystal is about 2.6 nm, and the particle size after accumulation is 153~284nm. -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is 313 mV, and it works stably for 378 hours.

[0058] Comparative Example 5 A method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method is provided, which specifically comprises the following steps: (1) Preparation of molten composite salt Weigh 5 g of sodium nitrate solid, mix well and place in a muffle furnace at 360 °C. The heating program of the muffle furnace is: heating rate of 20 °C / min, keeping warm for 20 min, to obtain a uniform molten composite salt.

[0059] (2) Preparation of short-range ordered iridium oxide Weigh 40 mg of IrCl3·H2O and add it to the molten composite salt obtained in step (1), continue heating for 5 min, and then cool naturally to room temperature; the product is washed with deionized water, filtered, and vacuum dried to obtain 30 mg of short-range ordered iridium oxide.

[0060] The particle size of a single nanocrystal is about 2.0 nm, and the particle size after accumulation is 137~255nm. -2 At a current density of , the overpotential of the short-range ordered iridium oxide in this embodiment is 268 mV, and it works stably for 500 h.

[0061] Comparative Example 6 5 mg of commercial IrO2 catalyst (purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., purity ≥99.9%, CAS number: 12030-49-8) was dispersed in 950 μL of ethanol solution (the volume ratio of ethanol to water was 1:1), and then 50 μL of Nafion solution was added and evenly dispersed in an ultrasonic machine; 4 μL of the dispersed solution was dropped on an area of ​​0.071 cm 2 The glassy carbon electrode was used as the working electrode, the reference electrode was a saturated silver chloride electrode, the counter electrode was a platinum wire, and the electrolyte was a 0.1 M HClO4 solution. A three-electrode test was performed on an electrochemical workstation (Chenhua 760E).

[0062] The average particle size after stacking is no more than 5 μm. -2 At a current density of , the overpotential of iridium oxide in comparative example 6 is 296 mV, and it works stably for 184 h.

[0063] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method, characterized in that: include: Step 1: adding an iridium source precursor to a molten composite salt and mixing the mixture, followed by cooling to obtain solid particles; The molten composite salt is a molten composite salt of sodium carbonate and sodium nitrate; Step 2: washing the solid particles obtained in step 1, and drying them to obtain short-range ordered iridium oxide; The particle size of the short-range ordered iridium oxide particles is 1.7 nm to 2.7 nm.

2. The method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method according to claim 1, characterized in that: The molten composite salt is obtained by mixing and calcining sodium carbonate and sodium nitrate, and the mass ratio of the sodium carbonate to the sodium nitrate is 1:1-49.

3. A method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method according to claim 2, characterized in that: The calcination temperature is 360°C to 500°C, and the calcination time is 20 min to 2 h.

4. The method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method according to claim 1, characterized in that: The iridium source precursor is any one of iridium trichloride hydrate, iridium trichloride and iridium dioxide.

5. The method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method according to claim 1, characterized in that: The mass ratio of the iridium source precursor to the molten composite salt is 1:100-150.

6. The method for rapidly preparing short-range ordered iridium oxide by a mixed molten salt method according to claim 1, characterized in that: In step 2, the drying is vacuum drying at 50°C to 100°C.

7. The short-range ordered iridium oxide obtained by the method described in any one of claims 1 to 6.

8. Use of the short-range ordered iridium oxide according to claim 7 in preparing anode catalytic materials for hydrogen production by proton exchange membrane water electrolysis.

9. A proton exchange membrane water electrolysis hydrogen production anode, characterized in that: It comprises an anode carrier and an anode catalytic material loaded thereon, wherein the anode catalytic material is the short-range ordered iridium oxide as claimed in claim 7.

10. A method for producing hydrogen by electrolysis of water using a proton exchange membrane, characterized in that: The proton exchange membrane water electrolysis hydrogen production anode as claimed in claim 9 is used, 0.1M HClO4 solution is used as the electrolyte, and a platinum mesh and an Ag / AgCl electrode are used as the counter electrode and the reference electrode respectively.

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