MoIrOx coating titanium fiber felt and preparation method and application thereof

Abstract

The invention belongs to the technical field of acidic electrolyzed water catalysts, and particularly discloses a MoIrOx coating titanium fiber felt and a preparation method and application thereof.The method comprises the following steps that iridium trichloride, ammonium molybdate tetrahydrate and ultrapure water are subjected to ultrasonic thorough dissolution; heating and activating in an oil bath pan; uniformly coating the mixture on the surface of the titanium fiber felt which is cleaned by acid washing through a spray gun; the titanium fiber felt is fixedly adsorbed in a drying oven to be thoroughly dried, and high-temperature calcination is conducted in a muffle furnace; and when the temperature of the muffle furnace is reduced to the taking-out temperature, the titanium fiber felt is taken out and washed with ultrapure water, and the washed titanium fiber felt is placed in a drying oven to be dried. According to the MoIrOx coating titanium fibrofelt as well as the preparation method and the application thereof, the performance and the stability of the original titanium fibrofelt are improved, and the MoIrOx coating titanium fibrofelt has excellent activity and stability under fluctuating current in a proton exchange membrane and is of great significance in promoting the wide commercialization process of a proton exchange membrane water electrolysis technology.

Description

Technical Field

[0001] The invention belongs to the technical field of acidic water electrolysis catalysts, and particularly relates to a MoIrOx-coated titanium fiber felt and a preparation method and application thereof. Background Art

[0002] Hydrogen is an ideal energy carrier and is considered one of the ultimate sustainable energy sources of the century. Among the various water electrolysis hydrogen production technologies, proton exchange membrane water electrolysis (PEMWE) cells offer advantages such as compactness, high efficiency, rapid response, a wide power range, and high hydrogen purity. These advantages effectively address the waste of intermittent and fluctuating renewable energy. The porous transport layer, a key component of PEMWE technology, serves as the medium between the catalyst layer and the flow field, facilitating water-gas transport, electrical conductivity, and heat conduction, profoundly impacting electrolyzer performance.

[0003] The anode reaction zone in PEMWE technology is a harsh environment characterized by high potential, high oxidation, and strong acidity, which places high demands on the corrosion resistance of the porous transport layer. Even the widely used titanium fiber felt can be corroded by the harsh anode environment, resulting in significant and irreversible loss of electrolytic cell performance. Therefore, it is necessary to design a highly active and corrosion-resistant coated titanium fiber felt to cope with the harsh environment of the anode zone, further improve electrolytic cell performance, and enhance energy efficiency.

[0004] The main method at present is to cover the surface of the original titanium fiber felt with a layer of corrosion-resistant platinum group metals, such as gold, platinum, iridium and other materials, through thermal decomposition, magnetron sputtering, PVD vapor deposition and other technologies. These platinum group metal protective layers can bring higher conductivity to obtain higher electrolytic cell performance, and can effectively inhibit the oxidation passivation of the surface layer of the titanium fiber felt. However, the high cost of platinum group metals will further increase the cost of PEMWE technology. Preparing a coating by mixed doping of metal oxides with good conductivity and corrosion resistance is a feasible solution. At present, there is an urgent need to develop low-platinum group precious metal coated titanium fiber felt with higher performance and corrosion resistance, which can improve the performance and stability of PEMWE while reducing the use of precious metals.

[0005] Therefore, the present invention needs to develop a MoIrOx coated titanium fiber felt and its preparation method and application, which can effectively solve the above problems. Summary of the Invention

[0006] The purpose of the present invention is to provide a MoIrOx-coated titanium fiber felt and its preparation method and application. The method improves the performance and stability of the original titanium fiber felt, has excellent activity and stability under fluctuating current in the proton exchange membrane (PEM), and is of great significance to promoting the widespread commercialization of proton exchange membrane water electrolysis (PEMWE) technology.

[0007] To achieve the above object, the present invention provides a MoIrOx coated titanium fiber felt, comprising the following steps:

[0008] Step S1: Iridium trichloride (IrCl3) and ammonium molybdate tetrahydrate ((NH4)6Mo7O 24 4H2O) was added into a beaker, and ultrapure water was added for ultrasonic dissolution to obtain solution A;

[0009] Step S2, placing solution A in an oil bath for heating and activation to obtain solution B;

[0010] Step S3, evenly coating the solution B on the surface of the titanium fiber felt after acid washing with a spray gun, and fixing the titanium fiber felt on the adsorption heating platform;

[0011] Step S4, drying the titanium fiber felt in an oven until the moisture content of the titanium fiber felt is less than 0.5%, and calcining the titanium fiber felt at a high temperature in a muffle furnace;

[0012] Step S5: When the temperature of the muffle furnace drops to the removal temperature, the titanium fiber felt is taken out and washed with ultrapure water. The washed titanium fiber felt is placed in an oven for drying to obtain MoIrOx coated titanium fiber felt.

[0013] Preferably, in step S1, the mass ratio of iridium trichloride to ammonium molybdate tetrahydrate is 8:1 to 4:1, and the amount of ultrapure water added is 15 to 20 mL;

[0014] The ultrasonic dissolution time is 30 minutes to ensure complete dissolution.

[0015] Preferably, in step S2, the heating temperature is 80-90° C., and the heating time is 48-50 h.

[0016] Preferably, in step S3, the pickling is specifically performed by soaking the surface of the titanium fiber felt in an oxalic acid solution with a mass fraction of 10% in an 80°C environment for 45 to 60 minutes; then taking it out, ultrasonically cleaning it with ultrapure water and anhydrous ethanol three times in sequence, and then storing it in an oven after drying.

[0017] Preferably, in step S3, the temperature of the adsorption heating platform is 100-120°C.

[0018] Preferably, in step S4, the calcination temperature is 350° C. and the calcination time is 30 min.

[0019] Preferably, in step S5, the taking-out temperature is 25-30°C, and the drying temperature is 55-60°C.

[0020] The present invention also provides a method for preparing a MoIrOx coated titanium fiber felt to prepare the obtained MoIrOx coated titanium fiber felt.

[0021] The present invention also provides a method for preparing a MoIrOx coated titanium fiber felt and application of the obtained MoIrOx coated titanium fiber felt in acidic electrolyzed water.

[0022] The present invention adopts the above-mentioned MoIrOx coated titanium fiber felt and its preparation method and application, and the beneficial effects are as follows:

[0023] (1) The present invention utilizes a spray thermal decomposition method to synthesize MoIrOx-coated titanium fiber felt for acidic water electrolysis. The preparation method uses iridium trichloride as an iridium source and ammonium molybdate tetrahydrate as a molybdenum source. Ultrapure water is added and ultrasonically dissolved, and the completely dissolved precursor is heated and activated in an oil bath. The activated precursors with different molybdenum-iridium content ratios are evenly coated on the surface of the titanium fiber felt after acid washing through a spray gun. After coating, the product is placed in an oven for thorough drying, and then annealed and calcined at high temperature to obtain the product, which is then washed with pure water to obtain the target product, MoIrOx-coated titanium fiber felt.

[0024] (2) The MoIrOx-coated titanium fiber felt prepared in the present invention exhibits excellent activity in a PEMWE system, and exhibits excellent activity and stability under long-term fluctuating current operation in a proton exchange membrane (PEM). The preparation method of the present invention is simple and efficient, and the prepared MoIrOx-coated titanium fiber felt catalyst has a stable structure and is easy to mass-produce.

[0025] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a SEM image of the MoIrOx coated titanium fiber felt prepared in Example 1 of the present invention, a MoIrOx coated titanium fiber felt, a preparation method thereof, and an application thereof;

[0027] Figure 2 This is a LSV test diagram of the OER of the MoIrOx coated titanium fiber felt prepared in Example 1 of the present invention, a preparation method thereof, and application thereof, and the original titanium fiber felt;

[0028] Figure 3 This is a graph showing the stability test of the MoIrOx coated titanium fiber felt in PEM prepared in the MoIrOx coated titanium fiber felt and its preparation method and application examples of the present invention;

[0029] Figure 4 This is a SEM image of the Mo2IrOx coated titanium fiber felt prepared in Example 2 of the present invention, a MoIrOx coated titanium fiber felt, a preparation method thereof, and an application thereof;

[0030] Figure 5This is a LSV test diagram of the OER of the Mo2IrOx coated titanium fiber felt prepared in Example 2 of the present invention, a MoIrOx coated titanium fiber felt, a preparation method thereof, and application thereof, and the original titanium fiber felt;

[0031] Figure 6 This is a graph showing the stability test of the Mo2IrOx coated titanium fiber felt prepared in Example 2 of the present invention, a MoIrOx coated titanium fiber felt, a preparation method thereof, and application thereof in a PEM;

[0032] Figure 7 This is a SEM image of a Mo4IrOx coated titanium fiber felt prepared in Example 3 of the present invention, a preparation method thereof, and application thereof;

[0033] Figure 8 This is a LSV test diagram of the OER of the Mo4IrOx coated titanium fiber felt prepared in Example 3 of the MoIrOx coated titanium fiber felt and its preparation method and application, and the original titanium fiber felt;

[0034] Figure 9 This is a graph showing the stability test of the Mo4IrOx coated titanium fiber felt prepared in Example 3 of the present invention, a MoIrOx coated titanium fiber felt, a preparation method thereof, and application thereof in a PEM;

[0035] Figure 10 This is an SEM image of a Mo8IrOx coated titanium fiber felt prepared in Example 4 of the present invention, a preparation method thereof, and application thereof;

[0036] Figure 11 This is a LSV test diagram of the OER of the Mo8IrOx coated titanium fiber felt prepared in Example 4 of the present invention, a MoIrOx coated titanium fiber felt, a preparation method thereof, and application thereof, and the original titanium fiber felt;

[0037] Figure 12 This is a stability test diagram of the Mo8IrOx coated titanium fiber felt prepared in Example 4 of the present invention, a MoIrOx coated titanium fiber felt, a preparation method thereof, and application thereof in PEM. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is further described below with reference to the accompanying drawings and embodiments.

[0039] Unless otherwise defined, technical or scientific terms used in the present invention shall have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

[0040] The iridium trichloride and ammonium molybdate tetrahydrate used in the present invention are both analytically pure.

[0041] Example 1

[0042] A method for preparing a MoIrOx coated titanium fiber felt comprises the following steps:

[0043] Step S1, 28mg IrCl3, 16mg (NH4)6Mo7O 24 4H2O was added to a beaker, and 10 mL of ultrapure water was added, mixed and dissolved by ultrasonication for 30 min until completely dissolved to obtain a precursor solution.

[0044] Step S2: Wrap the mouth of the beaker with tin foil after the completely dissolved precursor solution is placed in an 80° C. oil bath for heating and activation for 48 hours.

[0045] Step S3: Pickle the 5cm 2 The original titanium fiber felt is fixed on a heating platform at 120°C, and then the thoroughly activated precursor liquid is evenly sprayed on the surface of the titanium fiber felt through a spray gun.

[0046] Step S4: Dry the coated titanium fiber felt in an oven until the moisture content of the titanium fiber felt is less than 0.5%, place it in a crucible and calcine it in a muffle furnace at 450° C. for 30 minutes at a heating rate of 5° C. / min.

[0047] Step S5: When the temperature of the muffle furnace drops to 27° C., the titanium fiber felt is taken out, washed with ultrapure water, and then dried in an oven at 57° C. to obtain the MoIrOx coated titanium fiber felt.

[0048] The performance of the MoIrOx coated titanium fiber felt prepared in this example was tested.

[0049] (1) The MoIrOx coated titanium fiber felt prepared in Example 1 was subjected to field emission scanning electron microscopy (SEM). Figure 1 shown.

[0050] (2) The MoIrOx-coated titanium fiber felt prepared in Example 1 was used as a porous transport layer for PEM performance testing. The membrane electrodes used were all cathodes with 40% commercial platinum carbon and 1.25 mg cm -2 Loading: Commercial iridium dioxide anode, 0.8 mg cm -2 Load capacity.

[0051] like Figure 2 As shown, the MoIrOx coated titanium fiber felt prepared in Example 1 exhibits better water electrolysis performance than the original titanium fiber felt.

[0052] (III) The MoIrOx-coated titanium fiber felt prepared in Example 1 was used as a porous transmission layer to conduct a stability test of the fluctuating current protocol. The fluctuating current protocol was set at 0.1 Acm -2 ,0.5A cm -2,1A cm -2 ,1.5A cm -2 ,2A cm -2 ,2.5A cm -2 ,3A cm -2 The design is one cycle, where each current is maintained for 30 seconds. The entire stability test needs to run continuously for 2000 cycles. When recording every 100 cycles, at 3Acm -2 Voltage changes during the step.

[0053] like Figure 3 As shown, the MoIrOx coated titanium fiber felt prepared in Example 1 exhibits superior stability under fluctuating current than the original titanium fiber felt.

[0054] Example 2

[0055] A method for preparing Mo2IrOx coated titanium fiber felt comprises the following steps:

[0056] Step S1: 14 mg IrCl3, 16 mg (NH4)6Mo7O 24 4H2O was added to a beaker, and 10 mL of ultrapure water was added, mixed and dissolved by ultrasonication for 30 min until completely dissolved to obtain a precursor solution.

[0057] Step S2: Wrap the mouth of the beaker with tin foil after the completely dissolved precursor solution is placed in an 80° C. oil bath for heating and activation for 48 hours.

[0058] Step S3: Pickle the 5cm 2 The original titanium fiber felt is fixed on a heating platform at 120°C, and then the thoroughly activated precursor liquid is evenly sprayed on the surface of the titanium fiber felt through a spray gun.

[0059] Step S4: Dry the coated titanium fiber felt in an oven until the moisture content of the titanium fiber felt is less than 0.5%, place it in a crucible and calcine it in a muffle furnace at 450° C. for 30 minutes at a heating rate of 5° C. / min.

[0060] Step S5: When the temperature of the muffle furnace drops to 27°C, the titanium fiber felt is taken out, washed with ultrapure water, and then dried in an oven at 57°C to obtain the Mo2IrOx coated titanium fiber felt.

[0061] The Mo2IrOx coated titanium fiber felt prepared in this example was subjected to performance testing.

[0062] (1) The Mo2IrOx coated titanium fiber felt prepared in Example 2 was subjected to field emission scanning electron microscopy (SEM). Figure 4 shown.

[0063] (2) The Mo2IrOx-coated titanium fiber felt prepared in Example 2 was used as a porous transport layer for PEM performance testing. The membrane electrodes used were all cathodes with 40% commercial platinum carbon and 1.25 mg cm -2 Loading: Commercial iridium dioxide anode, 0.8 mg cm -2 Load capacity.

[0064] like Figure 5 As shown, the Mo2IrOx coated titanium fiber felt prepared in Example 2 exhibits better water electrolysis performance than the original titanium fiber felt.

[0065] (III) The Mo2IrOx coated titanium fiber felt prepared in Example 2 was used as a porous transmission layer to conduct a stability test of the fluctuating current protocol. The fluctuating current protocol was set at 0.1Acm -2 ,0.5A cm -2 ,1A cm -2 ,1.5A cm -2 ,2A cm -2 ,2.5A cm -2 ,3A cm -2 The design is one cycle, where each current is maintained for 30 seconds. The entire stability test needs to run continuously for 2000 cycles.

[0066] like Figure 6 As shown, the Mo2IrOx coated titanium fiber felt prepared in Example 2 exhibits superior stability under fluctuating current than the original titanium fiber felt.

[0067] Example 3

[0068] A method for preparing Mo4IrOx coated titanium fiber felt comprises the following steps:

[0069] Step S1: 7mg IrCl3, 16mg (NH4)6Mo7O 24 4H2O was added to a beaker, and 10 mL of ultrapure water was added, mixed and dissolved by ultrasonication for 30 min until completely dissolved to obtain a precursor solution.

[0070] Step S2: Wrap the mouth of the beaker with tin foil after the completely dissolved precursor solution is placed in an 80° C. oil bath for heating and activation for 48 hours.

[0071] Step S3: Pickle the 5cm 2 The original titanium fiber felt is fixed on a heating platform at 120°C, and then the thoroughly activated precursor liquid is evenly sprayed on the surface of the titanium fiber felt through a spray gun.

[0072] Step S4: Dry the coated titanium fiber felt in an oven until the moisture content of the titanium fiber felt is less than 0.5%, place it in a crucible and calcine it in a muffle furnace at 450° C. for 30 minutes at a heating rate of 5° C. / min.

[0073] Step S5: When the temperature of the muffle furnace drops to 27°C, the titanium fiber felt is taken out, washed with ultrapure water, and then dried in an oven at 57°C to obtain the Mo4IrOx coated titanium fiber felt.

[0074] The performance of the Mo4IrOx coated titanium fiber felt prepared in this example was tested.

[0075] (1) The Mo4IrOx coated titanium fiber felt prepared in Example 3 was subjected to field emission scanning electron microscopy (SEM). Figure 7 shown.

[0076] (2) The Mo4IrOx-coated titanium fiber felt prepared in Example 3 was used as a porous transport layer for PEM performance testing. The membrane electrodes used were all cathodes with 40% commercial platinum carbon and 1.25 mg cm -2 Loading: Commercial iridium dioxide anode, 0.8 mg cm -2 Load capacity.

[0077] like Figure 8 As shown, the Mo4IrOx coated titanium fiber felt prepared in Example 3 exhibits better water electrolysis performance than the original titanium fiber felt.

[0078] (III) The Mo4IrOx coated titanium fiber felt prepared in Example 3 was used as a porous transmission layer to conduct a stability test of the fluctuating current protocol. The fluctuating current protocol was set at 0.1Acm -2 ,0.5A cm -2 ,1A cm -2 ,1.5A cm -2 ,2A cm -2 ,2.5A cm -2 ,3A cm -2 The design is one cycle, where each current is maintained for 30 seconds. The entire stability test needs to run continuously for 2000 cycles.

[0079] like Figure 9 As shown, the Mo4IrOx coated titanium fiber felt prepared in Example 3 exhibits superior stability under fluctuating current than the original titanium fiber felt.

[0080] Example 4

[0081] A method for preparing Mo8IrOx coated titanium fiber felt comprises the following steps:

[0082] Step S1, 3.5mg IrCl3, 16mg (NH4)6Mo7O 24 4H2O was added to a beaker, and 10 mL of ultrapure water was added, mixed and dissolved by ultrasonication for 30 min until completely dissolved to obtain a precursor solution.

[0083] Step S2: Wrap the mouth of the beaker with tin foil after the completely dissolved precursor solution is placed in an 80° C. oil bath for heating and activation for 48 hours.

[0084] Step S3: Pickle the 5cm 2 The original titanium fiber felt is fixed on a heating platform at 120°C, and then the thoroughly activated precursor liquid is evenly sprayed on the surface of the titanium fiber felt through a spray gun.

[0085] Step S4: Dry the coated titanium fiber felt in an oven until the moisture content of the titanium fiber felt is less than 0.5%, place it in a crucible and calcine it in a muffle furnace at 450° C. for 30 minutes at a heating rate of 5° C. / min.

[0086] Step S5: When the temperature of the muffle furnace drops to 27°C, the titanium fiber felt is taken out, washed with ultrapure water, and then dried in an oven at 57°C to obtain the Mo8IrOx coated titanium fiber felt.

[0087] The performance of the Mo8IrOx coated titanium fiber felt prepared in this example was tested.

[0088] (1) The Mo8IrOx coated titanium fiber felt prepared in Example 4 was subjected to field emission scanning electron microscopy (SEM). Figure 10 shown.

[0089] (II) The Mo8IrOx-coated titanium fiber felt prepared in Example 4 was used as a porous transport layer for PEM performance testing. The membrane electrodes used were all cathodes with 40% commercial platinum carbon and 1.25 mg cm -2 Loading: Commercial iridium dioxide anode, 0.8 mg cm -2 Load capacity.

[0090] like Figure 11 As shown, the Mo8IrOx coated titanium fiber felt prepared in Example 4 exhibits better water electrolysis performance than the original titanium fiber felt.

[0091] (III) The Mo8IrOx coated titanium fiber felt prepared in Example 4 was used as a porous transmission layer to conduct a stability test of the fluctuating current protocol. The fluctuating current protocol was set at 0.1A cm -2 ,0.5Acm -2 ,1A cm -2 ,1.5A cm -2 ,2A cm -2 ,2.5A cm-2 ,3Acm -2 The design is one cycle, where each current is maintained for 30 seconds. The entire stability test needs to run continuously for 2000 cycles.

[0092] like Figure 12 As shown, the Mo8IrOx coated titanium fiber felt prepared in Example 4 exhibits superior stability under fluctuating current than the original titanium fiber felt.

[0093] Therefore, the present invention adopts the above-mentioned MoIrOx-coated titanium fiber felt and its preparation method and application. This method improves the performance and stability of the original titanium fiber felt, has excellent activity and stability under fluctuating current in proton exchange membrane (PEM), and is of great significance to promoting the widespread commercialization of proton exchange membrane water electrolysis (PEMWE) technology.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing MoIrOx coated titanium fiber felt, characterized in that: The following steps are involved: Step S1, adding iridium trichloride and ammonium molybdate tetrahydrate into a beaker, and adding ultrapure water for ultrasonic dissolution to obtain solution A; Step S2, placing solution A in an oil bath for heating and activation to obtain solution B; Step S3, evenly coating the solution B on the surface of the titanium fiber felt after acid washing with a spray gun, and fixing the titanium fiber felt on the adsorption heating platform; Step S4, drying the titanium fiber felt in an oven until the moisture content of the titanium fiber felt is less than 0.5%, and calcining the titanium fiber felt at a high temperature in a muffle furnace; Step S5: When the temperature of the muffle furnace drops to the removal temperature, the titanium fiber felt is taken out and washed with ultrapure water. The washed titanium fiber felt is placed in an oven for drying to obtain MoIrOx coated titanium fiber felt.

2. The method for preparing a MoIrOx coated titanium fiber felt according to claim 1, characterized in that: In step S1, the mass ratio of iridium trichloride to ammonium molybdate tetrahydrate is 8:1 to 4:1, and the amount of ultrapure water added is 15 to 20 mL; The ultrasonic dissolution time was 30 min.

3. The method for preparing a MoIrOx coated titanium fiber felt according to claim 1, characterized in that: In step S2, the heating temperature is 80-90°C and the heating time is 48-50 hours.

4. The method for preparing a MoIrOx coated titanium fiber felt according to claim 1, characterized in that: In step S3, the pickling is specifically performed by soaking the surface of the titanium fiber felt in an oxalic acid solution with a mass fraction of 10% at 80° C. for 45 to 60 minutes; then taking it out, ultrasonically cleaning it with ultrapure water and anhydrous ethanol three times in sequence, and then drying it in an oven for storage; Among them, the purity of anhydrous ethanol is 99.5%.

5. The method for preparing a MoIrOx coated titanium fiber felt according to claim 1, characterized in that: In step S3, the temperature of the adsorption heating platform is 100-120°C.

6. The method for preparing a MoIrOx coated titanium fiber felt according to claim 1, characterized in that: In step S4, the calcination temperature is 350° C. and the calcination time is 30 min.

7. The method for preparing a MoIrOx coated titanium fiber felt according to claim 1, characterized in that: In step S5, the taking-out temperature is 25-30°C, and the drying temperature is 55-60°C.

8. A method for preparing the MoIrOx coated titanium fiber felt according to any one of claims 1 to 7, wherein the MoIrOx coated titanium fiber felt is prepared.

9. A method for preparing the MoIrOx coated titanium fiber felt according to any one of claims 1 to 7, and use of the obtained MoIrOx coated titanium fiber felt in acidic electrolyzed water.

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