Preparation method of high-performance rare earth doped material self-humidifying membrane electrode

Abstract

The invention provides a preparation method of a high-performance rare earth doped material self-humidifying membrane electrode. The preparation method comprises the following steps: preparing anode catalyst slurry and cathode catalyst slurry by adopting a Pt / C catalyst; adding a nano hydrophilic material into the anode catalyst slurry to prepare anode intermediate slurry; adding dispersion liquid of a nano hydrophilic material and a rare earth doped material into the cathode catalyst slurry to prepare cathode intermediate slurry; the chemical formula of the rare earth doped material is Ce < 1-x > M < x > O < 2-beta >, M is one or two of Y and Gd, and x is more than or equal to 0.1 and less than or equal to 0.2; adding perfluorinated sulfonic acid resin dispersion liquid into the anode intermediate slurry to obtain anode slurry; adding perfluorinated sulfonic acid resin dispersion liquid into the cathode intermediate slurry to obtain cathode slurry; spraying the anode slurry and the cathode slurry to two sides of a proton exchange membrane; and placing the catalyst coating film in a plastic packaging frame, packaging, and attaching a gas diffusion layer. The water management capability of the membrane electrode can be improved, and the stability and the service life of the membrane electrode are improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of membrane electrodes, and particularly relates to a preparation method of a high-performance rare earth doped material self-humidifying membrane electrode. BACKGROUND

[0002] With the development of global industrialization, traditional fossil energy is facing depletion, and a large amount of pollutants generated by its combustion cause problems such as climate change and ecological destruction. Therefore, it is urgent to find clean and efficient new energy. Hydrogen fuel cells, as a device for directly converting hydrogen energy into electrical energy, have the advantages of high energy conversion efficiency and zero pollution emission, and are considered as one of the most potential new energies.

[0003] In a hydrogen fuel cell, a membrane electrode assembly (MEM) is a core component, and its performance directly affects the output power and stability of the entire fuel cell. The proton conduction ability of a proton exchange membrane is closely related to the water content, and a good wetting state can ensure its ideal mass transfer performance. However, in the actual operation process, the humidity control of the fuel cell inlet gas is relatively complex, and insufficient humidity will cause the proton exchange membrane to dehydrate and dry, which will reduce the proton conductivity and increase the internal resistance, and the performance of the battery will be reduced; too high humidity may cause water accumulation in the battery, which will hinder the gas diffusion and also affect the battery performance. Therefore, realizing the self-humidification function of the membrane electrode is of great significance to solve the water management problem of PEMFC.

[0004] At present, the research on self-humidifying membrane electrodes of hydrogen fuel cells mainly focuses on developing new self-humidifying materials, optimizing the structure of membrane electrodes and improving the preparation process, etc. For example, by adding hydrophilic nanoparticles in the proton exchange membrane, preparing a composite membrane, or introducing materials with moisture absorption and retention properties into the catalyst layer and gas diffusion layer, the self-humidification ability of the membrane electrode is enhanced. At the same time, researchers are also exploring the use of advanced micro-nano processing technology, surface modification technology, etc. to optimize the structure and performance of the membrane electrode, so as to further improve the self-humidification effect and battery performance.

[0005] However, under certain working conditions, such as high temperature and high current density, the self-humidifying membrane electrode may not provide enough water, causing the proton exchange membrane to dry out locally and affecting the performance of the battery. Under normal circumstances, catalysts (such as Pt particles) or hydrophilic materials (such as SiO2) will be added to the self-humidifying membrane to promote the generation and distribution of water. However, these materials may become catalysts for the generation of free radicals. Especially Pt particles or other metal materials, not only can catalyze the generation of water, but also can promote the decomposition of H2O2, thereby increasing the generation of free radicals, affecting the service life and reliability of the membrane electrode.

[0006] In addition, some research and production of self-humidifying membrane electrode need to invest a large amount of funds for purchasing advanced equipment, new materials and carrying out complex process development and optimization, which makes the manufacturing cost of the self-humidifying membrane electrode relatively high, and limits its large-scale commercial application. In addition, some high-performance self-humidifying materials and special structure design also increase the cost of the membrane electrode. SUMMARY

[0007] The purpose of the present application is to provide a high-performance rare earth doped material self-humidifying membrane electrode preparation method, which can improve the water management ability of the membrane electrode and improve the stability and life of the membrane electrode.

[0008] To achieve the above purpose, the present application is realized by the following technical scheme: A high-performance rare earth doped material self-humidifying membrane electrode preparation method, comprising the following steps: (1) Pt / C catalyst and solvent are used to prepare anode catalyst slurry and cathode catalyst slurry; (2) Nano-hydrophilic material is added to the anode catalyst slurry to prepare anode intermediate slurry; nano-hydrophilic material and a dispersion solution of rare earth doped material are added to the cathode catalyst slurry to prepare cathode intermediate slurry; the chemical formula of the rare earth doped material is Ce 1-x M x O 2-β , wherein M is one or both of Y and Gd, and 0.1≤x≤0.2; (3) Perfluorosulfonic acid resin dispersion solution is added to the anode intermediate slurry, and the anode slurry is obtained after treatment; perfluorosulfonic acid resin dispersion solution is added to the cathode intermediate slurry, and the cathode slurry is obtained after treatment; (4) The anode slurry and the cathode slurry are respectively sprayed to both sides of the proton exchange membrane to prepare a catalyst coated membrane with anode catalyst layer and cathode catalyst layer; (5) The catalyst coated membrane is placed in a plastic sealing frame, and after packaging, a gas diffusion layer is attached to obtain a self-humidifying membrane electrode.

[0009] The rare earth doped material Ce 1-x M x O 2-β of the present application has the following mechanism: cerium oxide itself is a fluorite structure, and there are a large number of oxygen vacancies on the surface of cerium oxide. These oxygen vacancies provide a large number of active sites for the adsorption, dissociation and transmission of oxygen. In the process of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), oxygen molecules can be adsorbed on the oxygen vacancies and dissociate and further react on the catalyst surface, thereby promoting the mass transfer of oxygen. The introduction of trivalent metal ions Y 3+ , Gd 3+, not only can increase the oxygen vacancy concentration, but also oxygen vacancy helps water adsorption and dissociation, thus generating protons, increasing the proton conductivity. In addition, Ce 3+ and Ce 2+ The change of valence state in the redox can eliminate the superoxide free radicals and hydroxyl radicals generated under adverse conditions, avoiding the attack of free radicals on the main chain and side chain of the proton exchange membrane, thus causing the thinning or even perforation of the membrane. The reaction mechanism is as follows: Preferably, the preparation method of the rare earth doped material comprises the following steps: 1) According to the stoichiometric ratio, the raw materials of organic metal oxide of Ce or nitrate of Ce and nitrate of M are weighed; 1-x M x O 2-β According to the stoichiometric ratio, the raw materials of organic metal oxide of Ce or nitrate of Ce and nitrate of M are weighed; 2) Dissolve the weighed raw materials in step 1) in water or ethanol, heat and stir until completely dissolved to obtain a precursor solution; 3) Add a complexing agent to the precursor solution and stir to form a transparent solution; 4) Add ammonia water to the transparent solution to adjust the pH value to 3-5; and continuously stir in a water bath at 60-95°C to form a gel; 5) Place the gel in step 4) for 18-24h, then dry it in an oven for 10-12h to obtain a dry gel; 6) Calcine the dry gel in step 5) at 350-400°C for 3-5h, cool to room temperature, and then calcine at 600-800°C for 5-7h to obtain the rare earth doped material.

[0010] Preferably, the complexing agent is citric acid, which is added in an amount of 2-3 times the total molar amount of Ce and M metal ions.

[0011] Preferably, the nano-hydrophilic material is silicon oxide.

[0012] Preferably, in the anode intermediate slurry, the mass ratio of Pt / C catalyst to nano-hydrophilic material is 1:(10-15); In the cathode intermediate slurry, the mass ratio of Pt / C catalyst to nano-hydrophilic material to rare earth doped material is 1:(35-50):15.

[0013] Preferably, in the anode catalyst slurry, the mass content of Pt / C catalyst is 35-45wt%; in the cathode catalyst slurry, the mass content of Pt / C catalyst is 55-65wt%. Specifically, for example, in the anode catalyst slurry, the mass content of Pt / C catalyst is 40wt%; in the cathode catalyst slurry, the mass content of Pt / C catalyst is 60wt%.

[0014] Preferably, the preparation method of the anode catalyst slurry and the cathode catalyst slurry both comprises the following steps: adding deionized water into the Pt / C catalyst, ultrasonic oscillation for 10-15 min, then adding anhydrous ethanol, isopropyl alcohol, and emulsifying in a homogenizing emulsifier for 0.5-1 h, and the emulsifying temperature is-5-2℃; the mass ratio of the deionized water, the anhydrous ethanol and the isopropyl alcohol is 15:1:(15-20).

[0015] Preferably, step (2) specifically comprises: adding the nano-hydrophilic material into the anode catalyst slurry to homogenize and emulsify, to obtain an anode intermediate slurry; adding the nano-hydrophilic material into the cathode catalyst slurry to homogenize and emulsify, and then adding the dispersion liquid of the rare earth doped material to homogenize and emulsify, to obtain a cathode intermediate slurry. The preparation method of the dispersion liquid of the rare earth doped material specifically comprises the following steps: weighing the rare earth doped material, deionized water and anhydrous ethanol with a mass ratio of 1:(2-4):1, and ultrasonic oscillation for 15-30 min.

[0016] Preferably, in step (3), the mass ratio of the anode intermediate slurry to the dispersion liquid of the perfluorosulfonic acid resin is 1:(6-10), and the mass ratio of the cathode intermediate slurry to the dispersion liquid of the perfluorosulfonic acid resin is 1:(4-8).

[0017] The beneficial effects of the present application are: 1. Improving oxygen mass transfer under high current density, and improving output performance.

[0018] 2. Eliminating adverse free radicals generated in the reaction process, and improving the stability and life of the membrane electrode.

[0019] 3. Enhancing the water management ability of the membrane electrode, widening the temperature working interval, and having a better application scenario. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 SEM image of the rare earth doped material Ce 0.85 Y 0.15 O 2-β prepared in Example 1; Figure 2 Another SEM image of the rare earth doped material Ce 0.85 Y 0.15 O 2-β prepared in Example 1; Figure 3 Polarization performance comparison chart of the single cell prepared by the membrane electrode in Example 1 and the single cell prepared by the membrane electrode in Comparative Example 1. DETAILED DESCRIPTION

[0021] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0022] Embodiment 1 A preparation method of a high-performance rare earth doped material self-humidifying membrane electrode, comprising the following steps: (1) preparing an anode catalyst slurry: adding deionized water into Pt / C catalyst, ultrasonic oscillation for 10 min, then adding anhydrous ethanol and isopropanol, and placing in a homogenizing emulsifier for emulsification for 1 h, and the emulsification temperature is-2℃; wherein the mass ratio of deionized water, anhydrous ethanol and isopropanol is 15:1:18; the mass content of Pt / C catalyst in the anode catalyst slurry is 40wt%; preparing a cathode catalyst slurry: adding deionized water into Pt / C catalyst, ultrasonic oscillation for 10 min, then adding anhydrous ethanol and isopropanol, and placing in a homogenizing emulsifier for emulsification for 1 h, and the emulsification temperature is-2℃; wherein the mass ratio of deionized water, anhydrous ethanol and isopropanol is 15:1:18; the mass content of Pt / C catalyst in the cathode catalyst slurry is 60wt%.

[0023] (2) adding hydrophilic material silicon oxide with an average particle size of 5nm into the anode catalyst slurry for homogenizing emulsification for 30 min to obtain an anode intermediate slurry; the mass ratio of Pt / C catalyst and hydrophilic material silicon oxide in the anode intermediate slurry is 1:10; adding hydrophilic material silicon oxide with an average particle size of 5nm into the cathode catalyst slurry for homogenizing emulsification for 30 min, then adding a dispersion liquid of rare earth doped material for homogenizing emulsification for 15 min to obtain a cathode intermediate slurry; the mass ratio of Pt / C catalyst, hydrophilic material silicon oxide and rare earth doped material in the cathode intermediate slurry is 1:40:15; The chemical formula of the rare earth doped material is Ce 0.85 Y 0.15 O 2-β ; the preparation method of the dispersion liquid of the rare earth doped material specifically comprises the following steps: weighing rare earth doped material, deionized water and anhydrous ethanol with a mass ratio of 1:2:1, and ultrasonic oscillation for 15 min.

[0024] (3) adding a mass fraction of 5% of a perfluorosulfonic acid resin dispersion liquid into the anode intermediate slurry for ultrasonic oscillation for 5 min to obtain an anode slurry; adding a mass fraction of 5% of a perfluorosulfonic acid resin dispersion liquid into the cathode intermediate slurry for ultrasonic oscillation for 5 min to obtain a cathode slurry; The mass ratio of the anode intermediate slurry to the perfluorosulfonic acid resin dispersion is 1:6, and the mass ratio of the cathode intermediate slurry to the perfluorosulfonic acid resin dispersion is 1:5.

[0025] (4) The anode slurry and the cathode slurry are respectively sprayed to both sides of the perfluorosulfonic acid proton exchange membrane to prepare a catalyst coating film with an anode catalyst layer and a cathode catalyst layer.

[0026] (5) The catalyst coating film is placed in a plastic sealing frame, and after the packaging is completed by a 150℃ overheat plastic machine, the carbon fiber paper gas diffusion layer is attached to the plastic sealing frame by using silicone glue, and the attachment is solidified to obtain a self-humidifying membrane electrode.

[0027] The preparation method of the rare earth doped material in the embodiment includes the following steps: 1) According to the chemical formula Ce 0.85 Y 0.15 O 2-β The raw materials cerium nitrate and yttrium nitrate are weighed according to the corresponding stoichiometric ratio; 2) The raw materials weighed in step 1) are dissolved in deionized water, heated and stirred until completely dissolved to obtain a precursor solution; the mass of deionized water is 4 times the total mass of the raw materials; 3) Citric acid is added to the precursor solution, and the molar amount of citric acid added is 3 times the total molar amount of cerium nitrate and yttrium nitrate, and the transparent solution is stirred; 4) Ammonia water is added to the transparent solution to adjust the pH value to 5; and continuously stirred in a 90℃ water bath for 3h to form a gel; 5) The gel in step 4) is left for 24h, and then placed in a 120℃ oven for drying for 12h to obtain a dry gel; 6) The dry gel in step 5) is calcined at 350℃ for 4h, cooled to room temperature, and then calcined at 600℃ for 5h to obtain the rare earth doped material.

[0028] Example 2: A high-performance rare earth doped material self-humidifying membrane electrode preparation method includes the following steps: (1) Preparation of anode catalyst slurry: deionized water is added to Pt / C catalyst, ultrasonic oscillation for 15min, then anhydrous ethanol, isopropyl alcohol are added, and emulsified in a homogenizing emulsifier for 0.5h, the emulsification temperature is 0℃; wherein the mass ratio of deionized water, anhydrous ethanol, isopropyl alcohol is 15:1:20; the mass content of Pt / C catalyst in the anode catalyst slurry is 40wt%; Preparation of cathode catalyst slurry: add deionized water to the Pt / C catalyst, ultrasonic oscillation for 15 min, then add anhydrous ethanol, isopropanol, and emulsify in a homogenizing emulsifier for 0.5 h, the emulsification temperature is 0℃; wherein the mass ratio of deionized water, anhydrous ethanol and isopropanol is 15:1:20; the mass content of Pt / C catalyst in the cathode catalyst slurry is 60wt%.

[0029] (2) Homogenize the anode catalyst slurry with hydrophilic material silicon oxide with an average particle size of 5 nm for 30 min to obtain an anode intermediate slurry; the mass ratio of Pt / C catalyst to hydrophilic material silicon oxide in the anode intermediate slurry is 1:15; After homogenizing the cathode catalyst slurry with hydrophilic material silicon oxide with an average particle size of 5 nm for 30 min, add the dispersion liquid of rare earth doped material to homogenize for 15 min to obtain a cathode intermediate slurry; the mass ratio of Pt / C catalyst to hydrophilic material silicon oxide to rare earth doped material in the cathode intermediate slurry is 1:50:15; The chemical formula of the rare earth doped material is Ce 0.85 Y 0.15 O 2-β , and the preparation method is the same as that of Example 1; the preparation method of the dispersion liquid of the rare earth doped material specifically includes the following steps: weigh the rare earth doped material, deionized water and anhydrous ethanol in a mass ratio of 1:2:1, and ultrasonic oscillation for 15 min.

[0030] (3) Add a mass fraction of 5% of the dispersion liquid of perfluorosulfonic acid resin to the anode intermediate slurry and ultrasonic oscillate for 5 min to obtain an anode slurry; add a mass fraction of 5% of the dispersion liquid of perfluorosulfonic acid resin to the cathode intermediate slurry and ultrasonic oscillate for 5 min to obtain a cathode slurry; Wherein, the mass ratio of the anode intermediate slurry to the dispersion liquid of perfluorosulfonic acid resin is 1:8, and the mass ratio of the cathode intermediate slurry to the dispersion liquid of perfluorosulfonic acid resin is 1:4.

[0031] (4) Spray the anode slurry and the cathode slurry to the two sides of the perfluorosulfonic acid proton exchange membrane respectively to prepare a catalyst coating film with an anode catalytic layer and a cathode catalytic layer.

[0032] (5) Place the catalyst coating film in a plastic sealing frame, and after packaging with a superheated plastic machine at 150℃, adhere the carbon fiber paper gas diffusion layer to the plastic sealing frame with silicone glue, and solidify the adhesion to obtain a self-humidifying membrane electrode.

[0033] Example 3: A method for preparing a high-performance rare earth doped material self-humidifying membrane electrode, comprising the following steps: (1) Preparing anode catalyst slurry: adding deionized water to Pt / C catalyst, ultrasonic oscillation for 10 min, then adding anhydrous ethanol, isopropyl alcohol, and placing in a homogenizing emulsifier for 1 h of emulsification, the emulsification temperature is-2℃; wherein the mass ratio of deionized water, anhydrous ethanol, isopropyl alcohol is 15:1:20; the mass content of Pt / C catalyst in the anode catalyst slurry is 40wt%; Preparation of cathode catalyst slurry: adding deionized water to Pt / C catalyst, ultrasonic oscillation for 10 min, then adding anhydrous ethanol, isopropyl alcohol, and placing in a homogenizing emulsifier for 1 h of emulsification, the emulsification temperature is-2℃; wherein the mass ratio of deionized water, anhydrous ethanol, isopropyl alcohol is 15:1:20; the mass content of Pt / C catalyst in the cathode catalyst slurry is 60wt%.

[0034] (2) Adding hydrophilic material silicon oxide with an average particle size of 5nm to the anode catalyst slurry and homogenizing for 30min to obtain an anode intermediate slurry; the mass ratio of Pt / C catalyst to hydrophilic material silicon oxide in the anode intermediate slurry is 1:10; After adding hydrophilic material silicon oxide with an average particle size of 5nm to the cathode catalyst slurry and homogenizing for 30min, adding a dispersion liquid of rare earth doped material and homogenizing for 15min to obtain a cathode intermediate slurry; the mass ratio of Pt / C catalyst to hydrophilic material silicon oxide to rare earth doped material in the cathode intermediate slurry is 1:35:15; The chemical formula of the rare earth doped material is Ce 0.85 Gd 0.15 O 2-β ; The preparation method of the dispersion liquid of the rare earth doped material specifically includes the following steps: weighing the rare earth doped material, deionized water and anhydrous ethanol with a mass ratio of 1:4:1, and ultrasonic oscillation for 15min.

[0035] (3) Adding a mass fraction of 5% of perfluorosulfonic acid resin dispersion liquid to the anode intermediate slurry and ultrasonic oscillation for 5min to obtain an anode slurry; adding a mass fraction of 5% of perfluorosulfonic acid resin dispersion liquid to the cathode intermediate slurry and ultrasonic oscillation for 5min to obtain a cathode slurry; Wherein, the mass ratio of the anode intermediate slurry to the perfluorosulfonic acid resin dispersion liquid is 1:10, and the mass ratio of the cathode intermediate slurry to the perfluorosulfonic acid resin dispersion liquid is 1:8.

[0036] (4) Spraying the anode slurry and the cathode slurry to both sides of the perfluorosulfonic acid proton exchange membrane respectively to prepare a catalyst coating film with an anode catalyst layer and a cathode catalyst layer.

[0037] (5) Put the catalyst coating film into the plastic sealing frame, and after completing the sealing by the over-heated plastic machine at 150℃, the carbon fiber paper gas diffusion layer is attached to the plastic sealing frame by using silicone glue, and curing is performed to obtain a self-humidifying membrane electrode.

[0038] The preparation method of the rare earth doped material in the embodiment includes the following steps: 1) The raw materials cerium nitrate and gadolinium nitrate are weighed according to the stoichiometric ratio of the chemical formula Ce 0.85 Gd 0.15 O 2-β The raw materials cerium nitrate and gadolinium nitrate are weighed according to the stoichiometric ratio of the chemical formula Ce 2) The raw materials weighed in step 1) are dissolved in deionized water, and heated and stirred until completely dissolved to obtain a precursor solution; the mass of deionized water is 4 times the total mass of the raw materials; 3) Citric acid is added to the precursor solution, and the molar amount of citric acid added is 2 times the total molar amount of cerium nitrate and gadolinium nitrate, and the solution is stirred to form a transparent solution; 4) Ammonia water is added to the transparent solution to adjust the pH value to 5, and the solution is continuously stirred in a water bath at 80℃ for 3h to form a gel; 5) The gel in step 4) is left to stand for 24h, and then placed in an oven at 120℃ for 12h to dry to obtain a dry gel; 6) The dry gel in step 5) is calcined at 350℃ for 4h, cooled to room temperature, and then calcined at 800℃ for 7h to obtain the rare earth doped material.

[0039] Comparative Example 1 The difference from Example 1 is that no dispersion liquid of the rare earth doped material is added to the cathode intermediate slurry.

[0040] That is, the preparation method of the cathode intermediate slurry includes the following steps: adding hydrophilic material silicon oxide with an average particle size of 5nm to the cathode catalyst slurry and homogenously emulsifying for 30min to obtain a cathode intermediate slurry; in the cathode intermediate slurry, the mass ratio of Pt / C catalyst to hydrophilic material silicon oxide is 1:40.

[0041] Single cell performance test: Single cells are prepared using the membrane electrodes in Example 1 and Comparative Example 1. The preparation method of the single cell is as follows: (1) cut the catalyst coating film (proton exchange membrane + two layers of catalyst layer) with an effective area of 5×5cm; (2) place the catalyst coating film into the plastic sealing frame, and complete the sealing by the over-heated plastic machine at 150℃; (3) attach the carbon fiber paper gas diffusion layer to the plastic sealing frame by using silicone glue, and perform curing to complete the preparation of the self-humidifying membrane electrode; (4) place the cathode and anode of the self-humidifying membrane electrode between the graphite electrode plates, and press the electrode plates with a pressing force of 0.13MPM to complete the preparation of the single cell.

[0042] Test condition: anode back pressure 80 kPa; cathode no back pressure; no additional humidification for both hydrogen and air; full open direct discharge structure for cathode; PTC assisted heating for temperature control.

[0043] Figure 3 Polarization performance curve of single cell at 70℃; Figure 3 The middle black curve is the polarization curve of the anode catalyst layer and the cathode catalyst layer only adding nano-hydrophilic material; the red curve is the polarization curve of the anode catalyst layer and the cathode catalyst layer both adding nano-hydrophilic material and simultaneously adding rare earth doped material in the cathode catalyst layer. As can be seen from the three graphs: compared with the performance of the cathode catalyst layer adding nano-hydrophilic material only, the oxygen mass transfer of the membrane electrode is obviously improved under large current density, because in the oxygen-deficient condition, Ce 4 ⁺can be reduced to Ce³⁺and release oxygen; while in the oxygen-rich environment, Ce³⁺can be re-oxidized to Ce 4 ⁺and absorb and store oxygen. This dynamic storage and release mechanism of oxygen helps to maintain the concentration gradient of oxygen and promotes the mass transfer of oxygen, especially when the demand for oxygen increases under large current density, Figure 3 The performance inflection point can be obviously seen in the middle, and the power density at 0.6V is 595 mW·cm -2 -2, 450 mW·cm -2 -2, respectively.

[0044] The above examples are only used to illustrate the technical solutions of the present application, but not limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing a high-performance self-humidifying membrane electrode of a rare earth-doped material, characterized by, The method comprises the following steps: (1) preparing an anode catalyst slurry and a cathode catalyst slurry by using a Pt / C catalyst and a solvent; (2) adding nano-hydrophilic material into the anode catalyst slurry to prepare anode intermediate slurry; adding nano-hydrophilic material and dispersion liquid of rare earth doped material into the cathode catalyst slurry to prepare cathode intermediate slurry; the chemical formula of the rare earth doped material is Ce 1-x M x O 2-β , wherein M is one or both of Y and Gd, and 0.1≤x≤0.

2. (3) adding a perfluorosulfonic acid resin dispersion liquid to the anode intermediate slurry to obtain an anode slurry, and adding a perfluorosulfonic acid resin dispersion liquid to the cathode intermediate slurry to obtain a cathode slurry; (4) spraying the anode slurry and the cathode slurry to two sides of a proton exchange membrane respectively to obtain a catalyst coated membrane with an anode catalyst layer and a cathode catalyst layer; (5) placing the catalyst coated membrane in a plastic sealing frame, and after packaging, attaching a gas diffusion layer to obtain a self-humidifying membrane electrode.

2. The method for preparing a high performance self-humidifying membrane electrode of rare earth doped material according to claim 1, characterized in that, The preparation method of the rare earth doped material comprises the following steps: 1) according to the chemical formula Ce 1-x M x O 2-β The raw materials, the organic metal oxide of Ce or the nitrate of Ce and the nitrate of M, are weighed according to the corresponding stoichiometric ratio. 2) Dissolve the weighed raw materials in step 1) in water or ethanol, heat and stir until completely dissolved to obtain a precursor solution; 3) Add a complexing agent to the precursor solution and stir to form a transparent solution; 4) Add ammonia water to the transparent solution to adjust the pH value to 3-5, and continuously stir in a water bath at 60-95°C to form a gel; 5) Place the gel in step 4) for 18-24 hours, then dry it in an oven for 10-12 hours to obtain a dry gel; 6) Calcine the dry gel in step 5) at 350-400°C for 3-5 hours, cool to room temperature, and then calcine at 600-800°C for 5-7 hours to obtain the rare earth doped material.

3. The method for preparing a high performance self-humidifying membrane electrode of rare earth doped material according to claim 2, characterized in that, The complexing agent is citric acid, which is added in an amount of 2-3 times the total molar amount of Ce and M metal ions.

4. The method for preparing a high-performance rare-earth-doped material self-humidifying film electrode according to claim 1, characterized in that, The nano-hydrophilic material is silicon oxide.

5. The method for preparing a high-performance rare-earth-doped material self-humidifying film electrode according to claim 1, characterized in that, In the anode intermediate slurry, the mass ratio of the Pt / C catalyst to the nano-hydrophilic material is 1:(10-15). In the cathode intermediate slurry, the mass ratio of the Pt / C catalyst to the nano-hydrophilic material to the rare earth doped material is 1:(35-50):

15.

6. The method for preparing a high-performance rare-earth-doped material self-humidifying film electrode according to claim 1, characterized in that, In the anode catalyst slurry, the mass content of the Pt / C catalyst is 35-45wt%; in the cathode catalyst slurry, the mass content of the Pt / C catalyst is 55-65wt%.

7. The method for preparing a high-performance self-humidifying membrane electrode of a rare earth doped material according to any one of claims 1 to 6, characterized in that, The preparation method of the anode catalyst slurry and the cathode catalyst slurry both comprises the following steps: adding deionized water to the Pt / C catalyst, ultrasonic oscillation for 10-15 minutes, then adding anhydrous ethanol and isopropanol, and emulsifying in a homogenizing emulsifier for 0.5-1 hour, with an emulsification temperature of-5-2°C; the mass ratio of the deionized water, the anhydrous ethanol and the isopropanol is 15:1:(15-20).

8. The method for preparing a high-performance self-humidifying membrane electrode of a rare earth doped material according to any one of claims 1 to 6, characterized in that, Step (2) specifically comprises: homogeneously emulsifying the nano-hydrophilic material in the anode catalyst slurry to obtain an anode intermediate slurry; homogeneously emulsifying the nano-hydrophilic material in the cathode catalyst slurry, and then adding a dispersion liquid of the rare earth doped material for homogenous emulsification to obtain a cathode intermediate slurry; The preparation method of the dispersion liquid of the rare earth doped material specifically comprises the following steps: weighing the rare earth doped material, deionized water and anhydrous ethanol in a mass ratio of 1:(2-4):1, and ultrasonic oscillation for 15-30 minutes.

9. The method for preparing a high-performance self-humidifying membrane electrode of a rare earth doped material according to any one of claims 1 to 6, characterized in that, In step (3), the mass ratio of the anode intermediate slurry to the perfluorosulfonic acid resin dispersion liquid is 1:(6-10), and the mass ratio of the cathode intermediate slurry to the perfluorosulfonic acid resin dispersion liquid is 1:(4-8).

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