Multi-component atomic hierarchy oxide solid solution integrated electrode for electrolyzed water, preparation method and application

Abstract

The invention discloses a multi-component atomic level oxide solid solution integrated electrode for electrolyzed water and a preparation method thereof, and belongs to the field of metal material surface plating. The electrode is composed of a gas diffusion layer, a nano array substrate and an atomic level oxide solid solution catalyst layer. The preparation method comprises the following steps: constructing a nano array microreactor on the surface of the gas diffusion layer; the method comprises the following steps: driving an atomic hierarchy solid solution to reconstruct by utilizing an array confinement effect through combination of precursor directional spraying and a heat treatment-rapid quenching process, and constructing a three-dimensional conformal ionomer network on the surface of the atomic hierarchy solid solution; and performing gold plating treatment on the back side of the electrode. Through the synergistic effect of spatial constraint and thermodynamic regulation of the nano microreactor, the traditional electrode interface mismatch bottleneck is broken through, and while precise construction of atomic-scale active sites is realized, the mechanical stability and oxygen evolution reaction kinetics of the electrode are improved. The preparation process has the advantages of controllable flow, strong large-scale expansibility and good industrial preparation prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of plating of metal materials, and in particular relates to a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis, a preparation method and an application thereof. Background Art

[0002] Energy is one of the core challenges facing human society today. Both production and daily life rely on energy. Currently, fossil fuels remain the primary energy source, but with the increasing prominence of environmental issues such as global warming, humanity's focus on and investment in green and clean energy has increased significantly. The development of green energy technologies has gradually replaced traditional fossil fuels and become a research focus. Hydrogen production by water electrolysis is an important green hydrogen production technology with broad market prospects. With its high current density, fast dynamic response speed, and good compatibility with renewable energy, it is considered the most promising hydrogen production technology for the future.

[0003] The catalytic layer is the place where the electrochemical reaction occurs in the electrolysis of water and is a key factor affecting the overall performance. The conventional catalytic layer is prepared by coating the catalyst onto the membrane. However, this method has extremely high requirements for slurry preparation, coating uniformity and coating parameters (such as thickness, drying conditions), and the preparation process is relatively complicated. During the coating and subsequent hot pressing process, the exchange membrane may be damaged by solvent penetration or mechanical pressure, resulting in performance degradation or shortened life. In addition, the catalytic layer prepared by this method has relatively few gas channels and a large gas and liquid transmission resistance. This resistance will significantly limit the overall performance of the electrolyzer.

[0004] There are currently some integrated membrane electrode structure designs. For example, in the prior art, an array structure is constructed on a Nafion membrane by transfer printing and other methods, and then hot-pressed to form an integrated membrane electrode, which greatly reduces the proton conduction resistance. In the prior art, TiO2 particles are also introduced into a Nafion emulsion, and then an array is constructed on the Nafion membrane by a template method to form an integrated membrane electrode, thereby enhancing the interface contact between the catalyst layer and the Nafion membrane. However, these methods are relatively complex, the process is relatively cumbersome, and it is difficult to achieve large-scale industrial-level preparation. For this reason, the present invention proposes a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis, a preparation method, and an application. Summary of the Invention

[0005] The purpose of the present invention is to provide a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis, a preparation method and application, which can construct an integrated electrode with the characteristics of high-density active sites of atomic-scale surface solid solution, enhanced diffusion and transfer of reactants and products, improved contact between various interfaces in the device, thereby achieving efficient synergy among the three, and the process is simple, which can achieve large-scale industrial-level preparation.

[0006] The technical solutions adopted by the present invention are as follows:

[0007] A multi-component atomic-level oxide solid solution integrated electrode for water electrolysis comprises a gas diffusion layer, a nano-array substrate grown on the surface of the gas diffusion layer, and a multi-component atomic-level oxide solid solution catalytic layer confinedly loaded on the heterogeneous interface of the nano-array substrate; wherein the crystal structure of the multi-component atomic-level oxide solid solution catalytic layer is an ordered crystalline phase or a disordered amorphous phase, and the nano-array substrate is composed of a metal oxide that can form strong chemical bonds with the gas diffusion layer and the catalytic layer.

[0008] Preferably, the array diameter in the nanoarray structure is 5-500 nanometers, and the array height is 0.1-5 micrometers; the thickness of the multi-component atomic-level oxide solid solution on the surface of the ordered crystalline phase multi-component atomic-level oxide solid solution is 0.5-10 nanometers.

[0009] A method for preparing a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis, the preparation method comprising the following steps:

[0010] Step 1: In situ growth of nanoarray substrate on the surface of the gas diffusion layer using a solvothermal method;

[0011] Step 2: spraying a multi-component catalyst precursor on one side of the substrate within the confined space of the nanoarray substrate;

[0012] Step 3: performing gradient heat treatment and quenching treatment on the electrode side of the multi-component catalyst precursor in sequence, driving the precursor to undergo atomic-level oxide solid solution crystal phase reconstruction in a confined space to form a catalytically active layer coupled with a heterogeneous interface;

[0013] Step 4: Construct a three-dimensional conformal ionomer network structure by in situ self-assembly on one side of the atomic-level catalytic layer.

[0014] Step 5: Finally, the integrated electrode is completed by directional gold plating on the opposite side of the catalyst layer through atomic layer deposition technology.

[0015] Preferably, the preparation of the nanoarray structure in step 1 includes the following steps: mixing an organic ketone solution with a volume ratio of (0.01-100): (0.01-100) with a titanium and ester solution, dispersing the mixture under 20-60kHz ultrasound for 10-30 minutes, and then standing for 1-3 hours; adding 1-100mL of a complexing agent solution with a concentration of 0.01-100mol / L, wherein the complexing agent is selected from at least one of citric acid, tartaric acid, gluconic acid, ethylenediaminetetraacetic acid and its sodium salt, and disodium nitrilotriacetate; transferring the mixed solution to a closed reactor containing a gas diffusion layer, and performing a solvent thermal reaction at 50-300°C for 1-12 hours to in situ grow an oriented nanoarray structure on the substrate surface.

[0016] Preferably, the preparation method of the catalyst precursor in step 2 includes: dispersing the multi-metal salt catalyst precursor in an alcohol solvent at a mass ratio of 1: (10-200), wherein the alcohol solvent is selected from at least one of ethanol, isopropanol, and ethylene glycol; forming a uniform slurry by ultrasonic dispersion at 20-60kHz for 0.5-1.5h; and depositing the slurry on the surface of the nanoarray by ultrasonic atomization spraying technology, controlling the carrier gas pressure to 0.1-0.5MPa, and the spraying time to 3-30min, to form a catalytic precursor layer with a thickness of 5-200nm.

[0017] Preferably, the treated gas diffusion layer is placed in an argon, hydrogen, nitrogen or air atmosphere and gradually heated to 100-500° C. and calcined for 1-60 min; the quenching treatment in step 3 adopts liquid nitrogen rapid cooling, ice water quenching or gradient temperature control cooling.

[0018] Preferably, in step 4, the construction of the three-dimensional conformal ionomer network structure comprises: mixing a perfluorosulfonic acid ionomer solution with a foaming agent in a volume ratio of (1-10):1, wherein the foaming agent is selected from at least one of sodium lauryl sulfate and perfluorooctane sulfonate; and using an ultrasonic-assisted atomization spraying process to control the ionomer loading to 0.01-1 mg / cm 2 , forming a three-dimensional network structure with a pore size of 50-500nm on the electrode surface.

[0019] Preferably, the directional gold plating treatment in step 5 adopts a magnetron sputtering process with a working pressure of 0.1-1 Pa, a sputtering power of 50-300 W, and a deposition time of 10-60 s to obtain a nano-gold modification layer with a thickness of 1-20 nm.

[0020] The invention discloses an application of a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis, wherein the multi-component atomic-level oxide solid solution integrated electrode is used as an integrated anode catalytic electrode or an integrated cathode catalytic electrode for water electrolysis.

[0021] The technical effects achieved by the present invention are:

[0022] The atomic-level integrated electrode prepared by the present invention improves the catalyst utilization rate and effectively increases the number of density active sites.

[0023] The atomic-level integrated electrode structure prepared by the present invention ensures a relatively vertical arrangement of the array surface, which is conducive to the discharge of gas and liquid; at the same time, it optimizes the gas diffusion layer-catalytic layer interface, making the bond more firm, which is conducive to resisting the impact of water flow and bubbles, avoiding falling off from the membrane, and providing a guarantee for achieving stability under high current.

[0024] The atomic-level integrated electrode prepared by the present invention improves the utilization rate of the catalyst and effectively increases the number of dense active sites; the atomic-level integrated electrode structure prepared by the present invention ensures that the array surface is arranged relatively vertically, which is conducive to the discharge of gas and liquid; at the same time, it optimizes the gas diffusion layer-catalytic layer interface, making the combination more firm, which is conducive to resisting the impact of water flow and bubbles, avoiding falling off from the membrane, and providing a guarantee for achieving stability under high current.

[0025] The present invention can construct an integrated electrode with the characteristics of high-density active sites of atomic-scale surface solid solution, enhanced diffusion and transfer of reactants and products, improved contact between various interfaces in the device, thereby achieving efficient synergy among the three. Moreover, the process is simple and can achieve large-scale industrial-level preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a TEM photograph of the atomic-level solid solution in Example 3 of the present invention;

[0027] Figure 2 is the LSV curve of PEMWE in Example 3 of the present invention;

[0028] Figure 3 is the stability curve of the PEMWE at different current densities in Example 3 of the present invention;

[0029] Figure 4 is the stability curve of PEMWE in Example 3 of the present invention;

[0030] Figure 5 This is a TEM photograph of the atomic-level solid solution in Example 4 of the present invention;

[0031] Figure 6 This is a comparison of the LSV curves of the main sample in Example 4 of the present invention and the commercial RuO2 catalyst;

[0032] Figure 7 This is a comparison of the stability curves of the main sample in Example 4 of the present invention and the commercial RuO2 catalyst;

[0033] Figure 8 This is a schematic diagram of the integrated electrode assembly in the fifth embodiment of the present invention;

[0034] Figure 9 is the LSV curve of PEMWE in Example 5 of the present invention;

[0035] Figure 10 This is the stability curve of PEMWE in Example 5 of the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is described in detail below with reference to the following examples. It should be understood that the following text is only used to describe one or more specific embodiments of the present invention and does not strictly limit the scope of protection of the present invention.

[0037] Example 1:

[0038] A multi-component atomic-level oxide solid solution integrated electrode for water electrolysis comprises a gas diffusion layer, a nano-array substrate grown on the surface of the gas diffusion layer, and a multi-component atomic-level oxide solid solution catalytic layer confinedly loaded on the heterogeneous interface of the nano-array substrate; wherein the crystal structure of the multi-component atomic-level oxide solid solution catalytic layer is an ordered crystalline phase or a disordered amorphous phase, and the nano-array substrate is composed of a metal oxide that can form strong chemical bonds with the gas diffusion layer and the catalytic layer.

[0039] The gas diffusion layer is made of any one of carbon paper, carbon cloth, nickel foam, nickel mesh, porous nickel sheet, titanium foam, porous titanium sheet, titanium mesh and titanium felt;

[0040] The nano array structure adopts any one of a nano cone array, a nano rod array, a nano wire array and a nano tube array.

[0041] The multi-component atomic-level oxide solid solution adopts any one or a combination of binary oxide solid solution, ternary oxide solid solution, quaternary oxide solid solution, pentacyclic oxide solid solution and hexacyclic oxide solid solution, and the crystal structure of the multi-component atomic-level oxide solid solution is an ordered crystalline phase or a disordered amorphous phase.

[0042] Preferably, the specific composition of the nanoarray structure is any one of tantalum pentoxide, niobium pentoxide, vanadium pentoxide, tungsten trioxide, titanium dioxide and tin dioxide; the metal elements in the multi-component atomic level oxide solid solution are: one or more combinations of ruthenium Ru, iridium Ir, cobalt Co, tin Sn, tantalum Ta, platinum Pt, iron Fe, nickel Ni, copper Cu, zinc Zn, tungsten W, chromium Cr, manganese Mn, vanadium V, strontium Sr, aluminum Al, magnesium Mg, titanium Ti, zirconium Zr, niobium Nb, molybdenum Mo, rhodium Rh, and palladium Pd.

[0043] Preferably, the array diameter in the nanoarray structure is 5-500 nanometers, and the array height is 0.1-5 micrometers; the thickness of the multi-component atomic-level oxide solid solution on the surface of the ordered crystalline phase multi-component atomic-level oxide solid solution is 0.5-10 nanometers.

[0044] Example 2:

[0045] A method for preparing a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis, the preparation method comprising the following steps:

[0046] Step 1: In situ growth of nanoarray substrate on the surface of the gas diffusion layer using a solvothermal method;

[0047] Step 2: spraying a multi-component catalyst precursor on one side of the substrate within the confined space of the nanoarray substrate;

[0048] Step 3: performing gradient heat treatment and quenching treatment on the electrode side of the multi-component catalyst precursor in sequence, driving the precursor to undergo atomic-level oxide solid solution crystal phase reconstruction in a confined space to form a catalytically active layer coupled with a heterogeneous interface;

[0049] Step 4: Construct a three-dimensional conformal ionomer network structure by in situ self-assembly on one side of the atomic-level catalytic layer.

[0050] Step 5: Finally, the integrated electrode is completed by directional gold plating on the opposite side of the catalyst layer through atomic layer deposition technology.

[0051] Preferably, the preparation of the nanoarray structure in step 1 includes the following steps: mixing an organic ketone solution with a volume ratio of (0.01-100): (0.01-100) with a titanium and ester solution, dispersing the mixture under 20-60kHz ultrasound for 10-30 minutes, and then standing for 1-3 hours; adding 1-100mL of a complexing agent solution with a concentration of 0.01-100mol / L, wherein the complexing agent is selected from at least one of citric acid, tartaric acid, gluconic acid, ethylenediaminetetraacetic acid and its sodium salt, and disodium nitrilotriacetate; transferring the mixed solution to a closed reactor containing a gas diffusion layer, and performing a solvent thermal reaction at 50-300°C for 1-12 hours to in situ grow an oriented nanoarray structure on the substrate surface.

[0052] The organic ketone solution is at least one of propionyl acetone, acetone, methyl ketone, cyclohexanone, butanone, hexanone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, isophorone, pyruvic acid, mesityl oxide, and benzyl acetone;

[0053] The ester solution is at least one of titanium isooctyl, titanium tetra-n-butoxide, titanium tert-butoxide, methyl titanium triisopropoxide, titanium n-propoxide, titanium tetraisopropoxide, tetrabutyl titanate, tetraethyl titanate, isopropyl titanate, polybutyl titanate, isopropyl titanium triisostearate, ethyl titanate, and tetraisopropyl titanate tungstic acid, or sodium tungstate solution, ammonium hydrogen tungstate solution, ammonium metatungstate solution, ammonium dodecatungstate solution, sodium niobate solution, potassium niobate solution, and tungstate niobate solution, with a solution concentration of 0.01-100 mol / L.

[0054] The complexing agent is at least one of citric acid, tartaric acid, gluconic acid, ethylenediaminetetraacetic acid, disodium ethylenediaminetetraacetic acid, tetrasodium ethylenediaminetetraacetic acid, and disodium nitrilotriacetic acid solution, and its concentration is 0.01-100 mol / l;

[0055] Preferably, the preparation method of the catalyst precursor in step 2 comprises: dispersing the multimetallic salt catalyst precursor in an alcohol solvent at a mass ratio of 1:(10-200), wherein the alcohol solvent is selected from at least one of ethanol, isopropanol, and ethylene glycol; forming a uniform slurry by ultrasonic dispersion at 20-60 kHz for 0.5-1.5 hours; depositing the slurry on the surface of the nanoarray by ultrasonic atomization spraying technology, controlling the carrier gas pressure to 0.1-0.5 MPa, and spraying for 3-30 minutes to form a catalytic precursor layer with a thickness of 5-200 nm;

[0056] The multi-metal salt catalyst precursor uses a metal salt component or a commercial catalyst slurry product; the metal salt components used are ruthenium trichloride, chlororuthenic acid, potassium chlororuthenate, sodium chlororuthenate, ammonium chlororuthenate, iridium trichloride, iridium tetrachloride, chloroiridic acid, potassium chloroiridate, sodium chloroiridate, ammonium chloroiridate, cobalt dichloride, cobalt sulfate, cobalt fluoride, cobalt nitrate, tin tetrachloride, stannous sulfate, stannous chloride, tantalum pentachloride, tantalum pentafluoride, chloroplatinic acid, chloroplatinous acid, potassium chloroplatinate, potassium chloroplatinate, sodium chloroplatinate, sodium chloroplatinous, ammonium chloroplatinate, ferrous sulfate, ferric sulfate, ferric chloride, ferrous chloride, nickel dichloride, nickel sulfate, nickel fluoride, copper dichloride, copper chloride, copper nitrate, cuprous nitrate, zinc dichloride, zinc sulfate, zinc fluoride, ammonium metatungstate, ammonium tungstate, tungsten hexachloride, disulfide At least one of tungsten chloride, chromium trichloride, chromium sulfate, manganese dichloride, manganese nitrate, manganese sulfate, vanadium chloride, vanadium nitrate, strontium chloride, strontium nitrate, strontium sulfate, aluminum trichloride, aluminum nitrate, aluminum sulfate, potassium aluminum sulfate dodecahydrate, magnesium dichloride, magnesium sulfate, magnesium nitrate, magnesium acetate, titanium tetrachloride, titanium sulfate, titanium nitrate, titanium trifluoride, calcium titanate, zirconium tetrafluoride, zirconium chloride, zirconium nitrate, zirconium sulfate, ammonium niobium sulfate, niobium pentachloride, sodium niobate, lithium niobate, molybdenum pentachloride, sodium molybdate, sodium molybdate dihydrate, ammonium molybdate, ammonium chloroaurate, rhodium sulfate, chlororhodic acid, potassium chlororhodate, sodium chlororhodate, ammonium chlororhodate, sodium chloropalladate, ammonium chloropalladate, potassium chloropalladate, sodium chloropalladate, ammonium chloropalladate, and palladium sulfate; the commercial cathode catalyst slurry product used is Pt / C;

[0057] Preferably, the treated gas diffusion layer is placed in an argon, hydrogen, nitrogen or air atmosphere and gradually heated to 100-500° C. and calcined for 1-60 min; the quenching treatment in step 3 adopts liquid nitrogen rapid cooling, ice water quenching or gradient temperature control cooling.

[0058] Preferably, in step 4, the construction of the three-dimensional conformal ionomer network structure comprises: mixing a perfluorosulfonic acid ionomer solution with a foaming agent in a volume ratio of (1-10):1, wherein the foaming agent is selected from at least one of sodium lauryl sulfate and perfluorooctane sulfonate; using an ultrasonic-assisted atomization spraying process, spraying 1-5 times, and controlling the ionomer loading to 0.01-1 mg / cm 2 , forming a three-dimensional network structure with a pore size of 50-500nm on the electrode surface.

[0059] The perfluorosulfonic acid ionomer solution is selected as a foaming agent: one or more of potassium perfluorobutanesulfonate (FC-98), potassium perfluorohexanesulfonate (FC-608), ethylene glycol (EG), dimethyl sulfoxide (DMSO), polytetrafluoroethylene dispersion (PTFE), polyperfluoroethylene propylene dispersion (FEP), and N-methylpyrrolidone (NMP).

[0060] Preferably, the directional gold plating treatment in step 5 adopts a magnetron sputtering process with a working pressure of 0.1-1 Pa, a sputtering power of 50-300 W, and a deposition time of 10-60 s to obtain a nano-gold modification layer with a thickness of 1-20 nm.

[0061] Example 3:

[0062] Step 1: First, titanium felt is selected as a gas diffusion layer, and then an oxide catalytic nanoarray structure is grown on the titanium felt. The specific process is as follows: the titanium felt is washed and dried; 5 ml of propionylacetone is selected as solution A; 2 ml of titanium tetraisopropoxide is selected as solution B; 30 ml of 0.01 mol / l disodium ethylenediaminetetraacetic acid solution is selected as the chelating agent; after mixing and stirring the above solutions, they are placed in a polytetrafluoroethylene reactor with the titanium felt as a gas diffusion layer, and reacted in a 100°C oven for 10 hours; after the reaction is completed, the titanium felt is taken out, washed, dried and set aside, and finally the nanoarray structure is grown on the titanium felt.

[0063] Step 2: Spray a catalyst precursor onto the titanium felt after the nanoarray structure is grown obtained in step 1; specifically, first prepare a catalyst slurry: weigh 6.15 mg of ruthenium trichloride RuCl3, 0.325 mg of tantalum pentachloride TaCl5, and 2.6 mg of iridium trichloride IrCl3, dissolve them in a mixed solution of 200 μl of concentrated hydrochloric acid and 300 μl of isopropanol, and ultrasonicate for 10-30 minutes to obtain an anode catalyst slurry;

[0064] Weigh 2 mg of Pt / C solution with a Pt content of 40% and dissolve it in a mixed solution of 200 μl of concentrated hydrochloric acid and 300 μl of isopropanol. Then add 10 μl of a binder, a perfluorosulfonic acid resin solution, and ultrasonicate for 10-30 minutes to obtain a cathode catalyst slurry. The binder in the catalyst precursor is a perfluorosulfonic acid resin solution, and its function is to effectively bond the catalyst particles and conduct protons.

[0065] Pt / C refers to a catalyst based on platinum (Pt) and supported on a carbon support. Specifically, it consists of platinum metal particles dispersed on a carbon material (such as activated carbon, carbon black, or carbon nanotubes), forming a composite material with excellent catalytic properties. In this embodiment, a Pt / C solution can also be used as the cathode catalyst.

[0066] The anode catalyst slurry was sprayed onto the titanium felt pre-treated in step 1 by an ultrasonic nozzle, and the Ru loading was 1 mg / cm 2 .

[0067] The cathode catalyst slurry was sprayed onto the proton exchange membrane through an ultrasonic nozzle as a catalytic cathode electrode, with a Pt loading of 0.8 mg / cm 2 .

[0068] Step 3: The titanium felt obtained above was placed in a tube furnace at 500° C. (Ar gas atmosphere) and calcined for 1 min.

[0069] Step 4: Take out the titanium felt treated in step 3 and let it cool naturally at room temperature.

[0070] Step 5: Remove the titanium felt treated in Step 4 and spray 20 μl of a mixed ionomer solution (15 μl of ionomer monomer (Nafion) solution + 5 μl of dimethyl sulfoxide (DMSO)) onto the catalyst layer to construct a porous ionomer network structure.

[0071] Step 6: Take out the titanium felt treated in step 5, and plate gold on the surface on the opposite side of the catalyst layer to obtain the prepared integrated anode electrode.

[0072] The prepared integrated anode electrode, proton exchange membrane coated with cathode catalyst and gas diffusion layer were assembled and PEMWE test was carried out.

[0073] from Figure 1 The transmission electron microscope (TEM) photograph shows that the catalyst atomic layer is an ordered crystalline phase and is firmly bonded to the support interface.

[0074] Figure 2 This is the LSV curve of the integrated anode electrode PEMWE in Example 3. The test conditions are: water flow rate of 10mL / min, test temperature of 80℃. It reaches 3Acm -2 Only 1.98V is required for high current density.

[0075] Figure 3 This is the stability test curve of the integrated anode electrode PEMWE at different current densities in Example 3. -2 The current density only slightly decreases.

[0076] Figure 4 This is the stability curve of PEMWE in Example 3 of the present invention.

[0077] Example 4:

[0078] Step 1: First, titanium felt is selected as a gas diffusion layer, and then an oxide catalytic nanoarray structure is grown on the titanium felt. The specific process is as follows: the titanium felt is washed and dried; 5 ml of propionylacetone is selected as solution A; 2 ml of titanium tetraisopropoxide is selected as solution B; 30 ml of 0.01 mol / l disodium ethylenediaminetetraacetic acid solution is selected as the chelating agent; after mixing and stirring the above solutions, they are placed in a polytetrafluoroethylene reactor with the titanium felt as a gas diffusion layer, and reacted in a 100°C oven for 10 hours; after the reaction is completed, the titanium felt is taken out, washed, dried and set aside, and finally the nanoarray structure is grown on the titanium felt.

[0079] Step 2: Prepare catalyst slurry: Weigh 2.58 mg of ruthenium trichloride RuCl3, 1.8 mg of cobalt nitrate Co(NO3)2, and 2.4 mg of zinc tetrachloride SnCl4 and dissolve them in a mixed solution of 200 μl of n-butanol, 150 μl of isopropanol, and 10 μl of concentrated hydrochloric acid. Ultrasonicate for 10-30 minutes to obtain anode catalyst slurry; use an ultrasonic nozzle to spray the anode catalyst slurry onto the titanium felt treated in advance in step 1, with a Ru loading of 1 mg / cm 2 ;

[0080] 2 mg of Pt / C solution (Pt content of 40%) was weighed and dissolved in a mixture of 200 μl of concentrated hydrochloric acid and 300 μl of isopropanol. 10 μl of a binder (perfluorosulfonic acid resin solution) was added and ultrasonicated for 10-30 minutes to obtain a cathode catalyst slurry. The cathode catalyst slurry was sprayed onto a proton exchange membrane using an ultrasonic nozzle. The Pt loading was 0.8 mg / cm 2 .

[0081] Step 3: The titanium felt was placed in a tube furnace (Ar atmosphere) at 500° C. and calcined for 1 min.

[0082] Step 4: Take out the titanium felt, immediately transfer it to liquid nitrogen, and rapidly cool it for 5-20 minutes.

[0083] Step 5: Remove the titanium felt and spray 50 μl of a mixed ionomer solution on the catalyst layer to construct a porous ionomer network structure. The mixed ionomer solution consists of 35 μl of ionomer monomer (Nafion) solution and 15 μl of dimethyl sulfoxide (DMSO).

[0084] Step 6: Take out the titanium felt treated in step 5, and plate gold on the surface on the opposite side of the catalyst layer to obtain the prepared integrated anode electrode.

[0085] The prepared integrated anode electrode, proton exchange membrane coated with cathode catalyst and gas diffusion layer were assembled and PEMWE test was carried out.

[0086] from Figure 5 The transmission electron microscope (TEM) photograph shows that the catalyst atomic layer is a disordered amorphous phase and is firmly bonded to the support interface.

[0087] Figure 6 This is a comparison of the LSV curves of the main sample in Example 4 of the present invention and the commercial RuO2 catalyst; the main sample has almost no attenuation after running for 500 hours;

[0088] Figure 7 This is a comparison of the stability curves of the main sample in Example 4 of the present invention and the commercial RuO2 catalyst; Figure 8The LSV curve of the integrated electrode in Example 4 under acidic conditions. Compared with commercial RuO2, the main sample has higher oxygen evolution activity. -2 The overpotential is 226 mV.

[0089] Embodiment 5:

[0090] Step 1: First, titanium felt is selected as a gas diffusion layer, and then an oxide catalytic nanoarray structure is grown on the titanium felt. The specific process is as follows: the titanium felt is washed and dried; 5 ml of propionylacetone is selected as solution A; 2 ml of titanium tetraisopropoxide is selected as solution B; 30 ml of 0.01 mol / l disodium ethylenediaminetetraacetic acid solution is selected as the chelating agent; after mixing and stirring the above solutions, they are placed in a polytetrafluoroethylene reactor with the titanium felt as a gas diffusion layer, and reacted in a 100°C oven for 10 hours; after the reaction is completed, the titanium felt is taken out, washed, dried and set aside, and finally the nanoarray structure is grown on the titanium felt.

[0091] Step 2: Prepare catalyst slurry: weigh 6.15 mg of ruthenium trichloride RuCl3, 0.325 mg of tantalum pentachloride TaCl5, and 2.6 mg of iridium trichloride IrCl3, dissolve them in a mixed solution of 70 μl of concentrated hydrochloric acid and 430 μl of isopropanol, and ultrasonicate for 10-30 minutes to obtain an anode catalyst slurry;

[0092] Weigh 2.2 mg of ruthenium trichloride RuCl3 and 4.2 mg of chloroplatinic acid H2PtCl6, dissolve them in a mixed solution of 300 μl of n-butanol and 200 μl of isopropanol, and ultrasonicate for 10-30 minutes to obtain a cathode catalyst slurry;

[0093] Step 3: Spray the anode catalyst slurry onto the titanium felt pre-treated in step 1 through an ultrasonic nozzle, with a Ru loading of 1 mg / cm 2 ;.

[0094] The titanium felt loaded with anode catalyst was placed in a muffle furnace (Ar atmosphere) at 500°C and calcined for 1 min.

[0095] The titanium felt was taken out and cooled naturally at room temperature.

[0096] The titanium felt was removed and 50 μl of a mixed ionomer solution was sprayed onto the catalyst layer to construct an ionomer network structure. The mixed solution consisted of 35 μl of ionomer monomer (Nafion) solution and 15 μl of N-methylpyrrolidone (NMP).

[0097] The titanium felt is taken out, and gold is plated on the surface of the opposite side of the catalyst layer to obtain the prepared integrated anode electrode.

[0098] Step 4: Use an ultrasonic nozzle to spray the cathode catalyst slurry onto the titanium felt pre-treated in step 1, with a Ru loading of 0.6 mg / cm 2 , Pt loading is 1.5 mg / cm 2 .

[0099] The titanium felt loaded with cathode catalyst was placed in a muffle furnace and calcined at 500° C. for 1 minute, then placed in a hydrogen atmosphere and calcined at 200° C. for 4 hours, and then taken out and naturally cooled at room temperature.

[0100] The titanium felt was taken out and 50 μl of ionomer mixed solution was sprayed on one side of the catalyst layer to construct an ionomer network structure to obtain the prepared integrated cathode electrode; the mixed solution was: 35 μl of ionomer monomer (Nafion) solution + 15 μl of N-methylpyrrolidone (NMP).

[0101] The titanium felt treated as above is taken out, and gold is plated on the surface on the opposite side of the catalyst layer to obtain the prepared integrated cathode electrode.

[0102] Step 5: Assemble the integrated anode electrode obtained in step 3 and the integrated cathode electrode obtained in step 4 and perform a PEMWE test.

[0103] Figure 8 This is a schematic diagram of the integrated electrode assembly in Example 5.

[0104] Figure 9 This is the LSV curve of the integrated electrode PEMWE in Example 3. -2 The decomposition voltage at a current density of is reduced to 1.79 V, which is a further improvement in performance compared to Example 3.

[0105] Figure 10 The integrated electrode 3Acm in Example 5 -2 Stability test curve under current density, almost no attenuation after 250h.

[0106] Example 6:

[0107] The invention discloses an application of a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis, wherein the multi-component atomic-level oxide solid solution integrated electrode is used as an integrated anode catalytic electrode or an integrated cathode catalytic electrode for water electrolysis.

[0108] In summary, the atomic-level integrated electrode prepared by the present invention improves the utilization rate of the catalyst and effectively increases the number of dense active sites; the atomic-level integrated electrode structure prepared by the present invention ensures that the array surface is arranged relatively vertically, which is conducive to the discharge of gas and liquid; at the same time, it optimizes the gas diffusion layer-catalytic layer interface, making the bonding stronger, which is conducive to resisting the impact of water flow and bubbles, avoiding falling off the membrane, and providing a guarantee for achieving stability under large current.

[0109] The foregoing is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art may make various improvements and modifications without departing from the principles of the present invention, and such improvements and modifications are also within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described or explained herein shall, unless otherwise specified or limited, be implemented in accordance with conventional means in the art.

Claims

1. A multi-component atomic-level oxide solid solution integrated electrode for water electrolysis, characterized by: It includes a gas diffusion layer, a nano-array substrate grown on the surface of the gas diffusion layer, and a multi-component atomic-level oxide solid solution catalytic layer confinedly loaded on the heterogeneous interface of the nano-array substrate; wherein the crystal structure of the multi-component atomic-level oxide solid solution catalytic layer is an ordered crystalline phase or a disordered amorphous phase, and the nano-array substrate is composed of a metal oxide that can form strong chemical bonds with the gas diffusion layer and the catalytic layer.

2. The multi-component atomic-level oxide solid solution integrated electrode for water electrolysis according to claim 1, characterized in that: The array diameter in the nanoarray structure is 5-500 nanometers, and the array height is 0.1-5 micrometers; the thickness of the multi-component atomic-level oxide solid solution on the surface of the ordered crystalline phase multi-component atomic-level oxide solid solution is 0.5-10 nanometers.

3. A method for preparing a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis, characterized in that: The multi-component atomic-level oxide solid solution integrated electrode is the multi-component atomic-level oxide solid solution integrated electrode according to any one of claims 1 to 2, and the preparation method comprises the following steps: Step 1: In situ growth of nanoarray substrate on the surface of the gas diffusion layer using a solvothermal method; Step 2: spraying a multi-component catalyst precursor on one side of the substrate within the confined space of the nanoarray substrate; Step 3: performing gradient heat treatment and quenching treatment on the electrode side of the multi-component catalyst precursor in sequence, driving the precursor to undergo atomic-level oxide solid solution crystal phase reconstruction in a confined space, thereby forming a catalytically active layer coupled with a heterogeneous interface; Step 4: Construct a three-dimensional conformal ionomer network structure by in situ self-assembly on one side of the atomic-level catalytic layer. Step 5: Finally, the integrated electrode is completed by directional gold plating on the opposite side of the catalyst layer through atomic layer deposition technology.

4. The method for preparing a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis according to claim 3, characterized in that: The preparation of the nanoarray structure in step 1 includes the following steps: mixing an organic ketone solution with a volume ratio of (0.01-100): (0.01-100) with a titanium and ester solution, dispersing the mixture by ultrasonication at 20-60kHz for 10-30 minutes, and then allowing the mixture to stand for 1-3 hours; adding 1-100mL of a complexing agent solution with a concentration of 0.01-100mol / L, wherein the complexing agent is selected from at least one of citric acid, tartaric acid, gluconic acid, ethylenediaminetetraacetic acid and its sodium salt, and disodium nitrilotriacetate; transferring the mixed solution to a closed reactor containing a gas diffusion layer, performing a solvent thermal reaction at 50-300°C for 1-12 hours, and in situ growing an oriented nanoarray structure on the substrate surface.

5. The method for preparing a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis according to claim 4, characterized in that: The preparation method of the catalyst precursor in step 2 includes: dispersing the multimetallic salt catalyst precursor in an alcohol solvent at a mass ratio of 1:(10-200), wherein the alcohol solvent is selected from at least one of ethanol, isopropanol, and ethylene glycol; forming a uniform slurry by ultrasonic dispersion at 20-60kHz for 0.5-1.5h; and depositing the slurry on the surface of the nanoarray by ultrasonic atomization spraying technology, controlling the carrier gas pressure to 0.1-0.5MPa and the spraying time to 3-30min, to form a catalytic precursor layer with a thickness of 5-200nm.

6. The method for preparing a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis according to claim 5, characterized in that: The treated gas diffusion layer is placed in an argon, hydrogen, nitrogen or air atmosphere and gradually heated to 100-500°C and calcined for 1-60 minutes; the quenching treatment in step 3 adopts liquid nitrogen rapid cooling, ice water quenching or gradient temperature control cooling.

7. The method for preparing a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis according to claim 6, characterized in that: In step 4, the construction of the three-dimensional conformal ionomer network structure includes: mixing a perfluorosulfonic acid ionomer solution with a foaming agent in a volume ratio of (1-10):1, wherein the foaming agent is selected from at least one of sodium lauryl sulfate and perfluorooctane sulfonate; using an ultrasonic-assisted atomization spraying process to control the ionomer loading to 0.01-1 mg / cm 2 , forming a three-dimensional network structure with a pore size of 50-500nm on the electrode surface.

8. The method for preparing a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis according to claim 7, characterized in that: The directional gold plating treatment in step 5 adopts a magnetron sputtering process with a working pressure of 0.1-1 Pa, a sputtering power of 50-300 W, and a deposition time of 10-60 s to obtain a nano-gold modification layer with a thickness of 1-20 nm.

9. An application of a multi-component atomic-level oxide solid solution integrated electrode for water electrolysis, characterized in that: The multi-component atomic-level oxide solid solution integrated electrode is the multi-component atomic-level oxide solid solution integrated electrode described in any one of claims 1-8, and the multi-component atomic-level oxide solid solution integrated electrode is used as an integrated anode catalytic electrode or an integrated cathode catalytic electrode for water electrolysis.

Images