Preparation method and application of PEM hydrogen production anode catalyst layer

Abstract

The application provides a preparation method of a PEM hydrogen production anode catalytic layer, and belongs to the technical field of membrane electrode preparation, and comprises the following steps: 1) surface treatment of a titanium plate; 2) uniformly mixing a titanium precursor, an iridium source, a metal salt and an acid solution to obtain a mixed solution; 3) drop-coating the obtained mixed solution on a PTL layer, i.e. the titanium plate, and performing high-temperature sintering to obtain an anode catalytic layer, and further combining the anode catalytic layer with a cathode to prepare a water electrolysis membrane electrode. The assembled PEM device is used for water electrolysis test. The results show that the anode catalytic layer prepared by the method has good water electrolysis performance and stability, and provides a new selection for the preparation of a commercial anode catalytic layer for water electrolysis hydrogen production, and has a wide market prospect.

Description

Technical Field

[0001] This invention belongs to the field of membrane electrode preparation technology, and particularly relates to a method for preparing a PEM hydrogen production anode catalyst layer and its application, specifically a method for preparing a low-iridium anode catalyst layer and its application in PEM hydrogen production. Background Technology

[0002] With the increasing demand for low-carbon emission reduction, green hydrogen production technologies have received widespread attention. Electrolysis of water using renewable energy is currently the hydrogen production process with the lowest carbon emissions among various technologies. Currently, hydrogen production via water electrolysis is mainly divided into alkaline water electrolysis (AWE), proton exchange membrane (PEM) water electrolysis, and solid oxide (SOE) water electrolysis. Compared to alkaline and SOE technologies, PEM water electrolysis equipment offers more flexible operation, tighter contact between components, lower resistance, and the ability to produce hydrogen at high current densities. More importantly, PEM electrolyzers have short response times, can tolerate power fluctuations, and can be perfectly coupled with renewable energy sources. In PEM hydrogen production devices, the anode catalyst layer is the key location for electrochemical reactions.

[0003] The main component of the anode catalyst layer is commonly IrO2, which exhibits good catalytic activity and stability. However, due to the limited reserves and high cost of iridium, the large-scale application of PEM (Proton Exchange Membrane) for hydrogen production via water electrolysis still faces significant challenges. Therefore, the development of low-iridium anode catalyst layers has become a current research hotspot. Currently, the preparation of the anode catalyst layer mainly involves directly coating the catalyst slurry onto the proton exchange membrane. However, the slurry often suffers from problems such as easy sedimentation, uneven spraying leading to increased contact resistance, and easy detachment of the catalyst layer, thus affecting catalytic performance. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a method for preparing a PEM hydrogen production anode catalyst layer and its application. The low-iridium anode catalyst layer prepared by the method provided by this invention has good PEM performance.

[0005] This invention provides a method for preparing a PEM hydrogen production anode catalyst layer, comprising:

[0006] A mixed solution is obtained by mixing a titanium precursor, an iridium source, a metal salt, and an acid solution.

[0007] The mixed solution was coated onto the surface of a titanium plate, dried, and calcined to directly prepare a catalyst layer on the PTL.

[0008] Preferably, the titanium precursor is selected from one or more of titanium chloride, titanium oxysulfate, and tetrabutyl titanate.

[0009] Preferably, the iridium source is selected from one or more of chloroiridium acid, iridium acetylacetonate, or iridium chloride.

[0010] Preferably, the metal salt is selected from one or more of carbonates, nitrates, and sulfates.

[0011] Preferably, the acid solution is selected from one or more of sulfuric acid solution and hydrochloric acid solution.

[0012] Preferably, the drying temperature is 80–150°C.

[0013] Preferably, the calcination temperature is 350–700°C.

[0014] Preferably, the calcination time is 0.5 to 5 hours.

[0015] This invention provides a low-iridium membrane electrode for water electrolysis, comprising: a PEM hydrogen production anode catalyst layer prepared by the method described above.

[0016] This invention provides an application of a low-iridium membrane electrode for water electrolysis in PEM hydrogen production;

[0017] The low-iridium membrane electrode for water electrolysis is the same as the low-iridium membrane electrode described in the above technical solution.

[0018] This invention provides a method for directly synthesizing a low-iridium catalyst as an anode catalyst layer on a Ti transport layer. The method involves directly drop-coating a precursor mixture solution for synthesizing the catalyst material onto a treated titanium plate to prepare the low-iridium anode catalyst layer. This preparation method is simple, stable, and reliable. The catalyst layer prepared using this method effectively avoids the problems of poor dispersibility and easy sedimentation of catalyst slurry during preparation. The prepared low-iridium anode catalyst layer exhibits good performance in PEM testing. Attached Figure Description

[0019] Figure 1 The image shows the XRD pattern of the IrO2@TiO2 catalyst layer prepared in Example 1 of this invention.

[0020] Figure 2 TEM image of the IrO2@TiO2 catalyst layer prepared in Example 1;

[0021] Figure 3 The graph shows the performance results of the low-iridium anode catalyst layers prepared for the examples and comparative examples in the PEM test. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] This invention provides a method for preparing a PEM hydrogen production anode catalyst layer, comprising:

[0024] A mixed solution is obtained by mixing a titanium precursor, an iridium source, a metal salt, and an acid solution.

[0025] The mixed solution was drop-coated onto the surface of a titanium plate, dried, and calcined to obtain a PEM hydrogen production anode catalyst layer.

[0026] In this invention, the titanium precursor is preferably selected from one or more of titanium chloride, titanium oxysulfate, and tetrabutyl titanate.

[0027] In this invention, the iridium source is preferably selected from one or more of chloroiridium acid, iridium acetylacetonate, or iridium chloride.

[0028] In this invention, the metal salt is preferably selected from one or more of carbonates, nitrates, and sulfates.

[0029] In this invention, the acid solution (solvent being water) is preferably one or more of sulfuric acid solution and hydrochloric acid solution; the concentration of the acid solution is preferably 0.02–0.5 mol / L, more preferably 0.05–0.4 mol / L, even more preferably 0.1–0.3 mol / L, and most preferably 0.2 mol / L.

[0030] In this invention, the molar ratio of the titanium precursor, iridium source, metal salt and acid in the acid solution is preferably (0.3-1):(0.2-1.5):(1-20):(0.5-1.5), more preferably (0.4-0.8):(0.5-1.0):(5-15):(0.8-1.2), and most preferably (0.5-0.7):(0.6-0.8):(8-12):1.

[0031] In this invention, the method for preparing the mixed solution preferably includes:

[0032] The tetrabutyl titanate, iridium acetylacetone, metal salt, and acid solution were stirred and thoroughly mixed to obtain a mixed solution.

[0033] In this invention, it is preferable to perform surface treatment on the titanium plate before using it to prepare the PEM hydrogen production anode catalyst layer; the surface treatment method preferably includes:

[0034] The titanium plate was treated in an acid solution, then boiled in an H2O2 solution, and then removed and cleaned.

[0035] In this invention, the acid in the acid solution (solvent being water) is preferably selected from sulfuric acid; the concentration of the acid solution is preferably 0.3 to 0.7 mol / L, more preferably 0.5 mol / L.

[0036] In this invention, the processing temperature is preferably 70-90°C, more preferably 75-85°C, and most preferably 80°C; the processing time is preferably 1-3 hours, more preferably 1.5-2.5 hours, and most preferably 2 hours.

[0037] In this invention, the mass concentration of the H2O2 solution (with water as the solvent) is preferably 30%.

[0038] In this invention, the cooking temperature is preferably 70-90°C, more preferably 75-85°C, and most preferably 80°C; the cooking time is preferably 0.5-1.5 hours, and more preferably 1 hour.

[0039] In this invention, the cleaning reagent is preferably water and ethanol, and the water is preferably deionized water; the cleaning method is preferably ultrasonic cleaning.

[0040] In this invention, the oxide layer and impurities on the surface of the titanium plate are removed by surface treatment.

[0041] In this invention, the coating is preferably performed by drop coating on the surface of a titanium plate.

[0042] In this invention, the drying is preferably oven drying, and the drying temperature is preferably 80-150°C, more preferably 90-140°C, even more preferably 100-130°C, and most preferably 110-120°C.

[0043] In this invention, the calcination is preferably carried out in an air atmosphere; the calcination temperature is preferably 350-700°C, and most preferably 400°C; the calcination time is preferably 0.5-3 hours, and most preferably 1.5 hours.

[0044] In this invention, the iridium loading in the catalyst layer is preferably 0.2–0.4 mg / cm³. 2 More preferably 0.3 mg / cm³ 2 .

[0045] This invention provides a low-iridium membrane electrode for water electrolysis, comprising: a PEM hydrogen production anode catalyst layer prepared by the method described above.

[0046] In this invention, the low-iridium membrane electrode for water electrolysis preferably further includes a cathode catalyst layer.

[0047] In this invention, the method for preparing the cathode catalyst layer preferably includes:

[0048] The cathode catalyst, isopropanol, and Nafion (a perfluorosulfonic acid polymer) were mixed to obtain a mixture.

[0049] The mixture is coated onto one side of a proton exchange membrane to obtain a cathode catalyst layer.

[0050] In this invention, the cathode catalyst is preferably a Pt / C catalyst; the concentration of the Pt / C catalyst is preferably 35-45%, more preferably 40%.

[0051] In this invention, the mass of the isopropanol is preferably 26 to 36 times the mass of the anode catalyst, more preferably 30 times.

[0052] In this invention, the concentration of Nafion is preferably 5%.

[0053] In this invention, the mass of the Nafion is preferably 1 / 5 to 1 / 7 of the mass of the cathode catalyst, more preferably 1 / 6.

[0054] In this invention, the proton exchange membrane is preferably N117.

[0055] In this invention, the platinum loading in the cathode catalyst layer is preferably 0.2–0.4 mg / cm³. 2 More preferably 0.3 mg / cm³ 2 .

[0056] In this invention, the water electrolysis low-iridium membrane electrode is preferably obtained by assembling the PEM hydrogen production anode catalyst layer and the cathode catalyst layer; the assembled water electrolysis low-iridium membrane electrode is preferably PTL (titanium plate)-anode catalyst-Nafion membrane (N117)-cathode catalyst-cathode diffusion layer.

[0057] This invention provides an application of a low-iridium membrane electrode for water electrolysis in proton exchange membrane water electrolysis for hydrogen production;

[0058] The low-iridium membrane electrode for water electrolysis is the same as the low-iridium membrane electrode described in the above technical solution.

[0059] In this invention, the low-iridium film electrode is used for PEM hydrogen production, where oxygen is generated at the anode and hydrogen is generated at the cathode.

[0060] This invention employs a method of directly drop-coating a precursor mixture solution for synthesizing catalytic materials onto a treated titanium plate to prepare a low-iridium anode catalytic layer. The preparation method is simple, stable, and reliable. The catalytic layer prepared using the method provided by this invention effectively avoids the problems of poor dispersibility and easy sedimentation of catalyst slurry during the preparation process. The prepared low-iridium anode catalytic layer exhibits good performance in PEM testing.

[0061] Example 1

[0062] First, the titanium plate is surface treated by placing it in a 0.5 mol / L sulfuric acid solution at 80°C for 2 hours, and then immersing it in a 30% H2O2 solution at 80°C for 1 hour to remove the oxide layer and impurities on the surface. After removal, it is ultrasonically cleaned with deionized water and ethanol and set aside for use.

[0063] 2.56 mmol of tetrabutyl titanate, 5.12 mmol of iridium acetylacetone, 23.04 mmol of sodium nitrate and 3 mmol of sulfuric acid solution (the concentration of sulfuric acid solution is 0.5 mol / L, and the sulfuric acid in it is 3 mmol) were stirred and mixed thoroughly to obtain a mixed solution;

[0064] The prepared mixed solution was drop-coated onto a titanium plate, dried in an oven at 110°C, and then calcined in an air environment in a high-temperature furnace at 400°C for 1 hour. This process was repeated 5 times to obtain the anode catalyst layer with an iridium loading of approximately 0.3 mg / cm³. 2 .

[0065] Figure 1 IrO2@TiO2(n) prepared in Example 1 IrO2 :n TiO2 XRD pattern of (2:1) Figure 2 The TEM image of IrO2@TiO2 prepared in Example 1 is shown below. Figure 1 and Figure 2 It can be seen that IrO2@TiO2 was successfully prepared.

[0066] The platinum loading per unit electrode area is 0.3 mg / cm². 2 A 40% Pt / C catalyst was mixed with 30 times the mass of isopropanol and 1 / 6 the mass of 5% Nafion. The mixture was then coated onto one side of a proton exchange membrane N117 as a cathode catalyst layer.

[0067] The prepared anode catalyst layer was assembled with the cathode catalyst layer prepared in Example 1 and subjected to PEM testing. Polarization curves for water electrolysis were obtained at 60°C, with a polarization rate of 2 A / cm. 2 At a current density of 1.93V, the test voltage is 1.93V. Figure 3 As shown, by Figure 3 It can be seen that the low-iridium anode catalyst layer prepared in Example 1 has good catalytic activity in the PEM test.

[0068] Example 2

[0069] First, the titanium plate is surface treated by placing it in a 0.5 mol / L sulfuric acid solution at 80°C for 2 hours, and then immersing it in a 30% H2O2 solution at 80°C for 1 hour to remove the oxide layer and impurities on the surface. After removal, it is ultrasonically cleaned with deionized water and ethanol and set aside for use.

[0070] 5.12 mmol of tetrabutyl titanate, 2.56 mmol of iridium acetylacetonate, 11.52 mmol of sodium nitrate and 6 mmol of sulfuric acid solution (the concentration of sulfuric acid solution is 0.5 mol / L, and the sulfuric acid in it is 6 mmol) were stirred and mixed thoroughly to obtain a mixed solution;

[0071] The mixed solution prepared above was drop-coated onto a titanium plate, dried in an oven at 110°C, and then calcined in an air environment in a high-temperature furnace at 400°C for 1 hour. This process was repeated 8 times to obtain the anode catalyst layer (n). IrO2 :n TiO2 =1:2), iridium loading is approximately 0.2–0.3 mg / cm³. 2 .

[0072] The anode catalyst layer prepared in Example 2 of this invention was subjected to PEM testing according to the method of Example 1, and the test results are as follows: Figure 3 As shown.

[0073] Comparative Example 1

[0074] Take tetrabutyl titanate, iridium acetylacetone, metal salt and sulfuric acid solution and stir and mix them thoroughly (the ratio and amount of all raw materials are the same as in Example 1) to obtain a mixed solution. After evaporating to dryness at 80°C, it is calcined at high temperature in a muffle furnace at 400°C for 1 hour to obtain IrO2 / TiO2 catalyst.

[0075] IrO2 / TiO2 catalyst, binder Nafion, and isopropanol / water were mixed (mass ratio 50:4:8) and ultrasonically dispersed for 1 hour to obtain the anode slurry.

[0076] The cathode slurry was prepared in the same manner as in Example 1.

[0077] Ultrasonic spraying equipment was used to spray the cathode and anode catalyst slurries onto both sides of the proton exchange membrane N117. The spraying process was carried out on the adsorption heating plate at a temperature of 80°C, and a dedicated spraying film forming equipment was used to spray the cathode and anode slurries.

[0078] The membrane electrode prepared in Comparative Example 1 of the present invention was subjected to PEM testing according to the method of Example 1. The test results are as follows: Figure 3 As shown.

[0079] Comparative Example 2

[0080] Commercial IrO2, binder Nafion, and isopropanol / water were mixed (mass ratio 50:4:8) and ultrasonically dispersed for 1 hour to obtain an anode slurry.

[0081] The cathode slurry was prepared in the same manner as in Example 1.

[0082] Ultrasonic spraying equipment was used to spray the cathode and anode catalyst slurries onto both sides of the proton exchange membrane N117. The spraying process was carried out on the adsorption heating plate at a temperature of 80°C, and a dedicated spraying film forming equipment was used to spray the cathode and anode slurries.

[0083] The membrane electrode prepared in Comparative Example 2 of the present invention was subjected to PEM testing according to the method of Example 1. The test results are as follows: Figure 3 As shown.

[0084] This invention employs a method of directly drop-coating a precursor mixture solution for synthesizing catalytic materials onto a treated titanium plate to prepare a low-iridium anode catalytic layer. The preparation method is simple, stable, and reliable. The catalytic layer prepared using the method provided by this invention effectively avoids the problems of poor dispersibility and easy sedimentation of catalyst slurry during the preparation process. The prepared low-iridium anode catalytic layer exhibits good performance in PEM testing.

[0085] While the invention has been described and illustrated with reference to specific embodiments thereof, such description and illustration are not intended to limit the invention. It will be readily understood by those skilled in the art that various changes may be made to suit particular circumstances, materials, compositions, substances, methods, or processes to the objectives, spirit, and scope of this application without departing from the true spirit and scope of the invention as defined by the appended claims. All such modifications are intended to be within the scope of the appended claims. Although the methods disclosed herein have been described with reference to specific operations performed in a particular order, it should be understood that these operations may be combined, subdivided, or reordered to form equivalent methods without departing from the teachings of the invention. Therefore, unless specifically indicated herein, the order and grouping of operations are not a limitation of this application.

Claims

1. A method for preparing a PEM hydrogen production anode catalytic layer, comprising: mixing a titanium precursor, an iridium source, a metal salt and an acid solution to obtain a mixed solution; and dropping the mixed solution onto a titanium plate surface, drying and calcining to obtain a PEM hydrogen production anode catalytic layer. The iridium source is selected from one or more of chloro iridic acid, acetylacetone iridium or iridium chloride; the metal salt is selected from one or more of carbonate, nitrate, sulfate; and the acid solution is selected from one or more of sulfuric acid solution and hydrochloric acid solution. The titanium precursor is selected from one or more of titanium chloride, titanyl sulfate and n-butyl titanate. The molar ratio of the titanium precursor, the iridium source, the metal salt and the acid in the acid solution is (0.3-1) : (0.2-1.5) : (1-20) : (0.5-1.5). The drying temperature is 80-150℃. The calcining temperature is 400-600℃.

2. The method of claim 1, wherein, The calcining time is 0.5-5h.

3. The method of claim 1, wherein, The PEM hydrogen production anode catalytic layer prepared by the method of claim 1.

4. The method of claim 1, wherein, 6.An application of an electrolytic water low iridium membrane electrode in PEM hydrogen production.

5. An electrolytic water low-iridium membrane electrode comprising: The electrolytic water low iridium membrane electrode is the electrolytic water low iridium membrane electrode of claim 5. ​ ​

Images