Method for preparing membrane electrode of anion exchange membrane electrolytic cell from transition metal sulfide Co-MoS2
By preparing Co-doped MoS2 catalyst combined with anion exchange membrane, the problem of high cost of precious metal catalysts is solved, low-cost and efficient electrolytic performance and stability is achieved, and it is suitable for mass production of anion exchange membrane electrolytic cells.
Patent Information
- Application Number
- CN202510672901.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-23
- Publication Date
- 2025-08-15
AI Technical Summary
In the prior art, precious metal Ru/Ir-based materials are costly and scarce, and it is difficult to find cheap and excellent performance non-precious metal catalysts to replace them in anion exchange membrane electrolytic cells, and traditional methods are difficult to effectively improve the activity and stability of the catalyst.
Cobalt chloride hexahydrate, ammonium molybdate tetrahydrate, and thiourea thiourea are used as raw materials to prepare Co-doped MoS2 catalysts through hydrothermal reactions, and mixed with conductive carbon black, anion exchange liquid, etc., sprayed on the anion exchange membrane to form a film electrode, optimizing the chemical composition and structure of the catalyst.
It achieves low-cost and efficient electrolytic performance, and the catalyst is not easy to fall off. It is suitable for mass production and has good electrolytic performance and stability.
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Figure CN120485848A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of electrochemical technology, and in particular to a method for preparing an anion exchange membrane electrolyzer membrane electrode from transition metal sulfide Co-MoS2. Background Art
[0002] Traditional fossil energy emits greenhouse gases and causes environmental pollution during the conversion into heat and electricity. Hydrogen, as a clean energy source, has the advantages of high energy density and zero carbon emissions, and is of great significance to achieving the goal of carbon neutrality. Low-temperature water electrolysis system is an important method for preparing green hydrogen. Anion exchange membrane electrolyzers can allow the use of non-precious metal catalysts for water electrolysis reactions, and overcome the problem that alkaline electrolyzers must use concentrated alkali, which can reduce costs and alleviate corrosion problems. Compared with precious metal catalysts, the low mass specific activity of non-precious metals requires a higher loading amount. Therefore, optimizing the chemical composition, catalytic activity and stability of non-precious metal catalysts is the key to improving the performance of anion exchange membrane electrolyzers.
[0003] Currently, Ru / Ir-based materials can effectively catalyze the oxygen evolution reaction, but they are expensive and relatively scarce. Therefore, there is a need to find inexpensive and high-performance non-precious metal catalysts to replace precious metal materials. Transition metal sulfides have good conductivity and relatively mild synthesis processes. They can be prepared through hydrothermal synthesis, gas sulfurization, and template methods. Through methods such as doping, heterostructures, and defect engineering, the active sites of the catalyst can be modulated to promote charge transfer. At the same time, a stable structure can be formed within the catalyst to reduce sulfur loss, thereby improving its activity and stability in the electrocatalytic water splitting reaction. Summary of the Invention
[0004] (1) Technical problems solved
[0005] In view of the shortcomings of the existing technology, the present invention provides a method for preparing anion exchange membrane electrolyzer membrane electrode using transition metal sulfide Co-MoS2.
[0006] (2) Technical solution
[0007] A method for preparing an anion exchange membrane electrolyzer membrane electrode from transition metal sulfide Co-MoS2 comprises the following steps:
[0008] Step 1: Using cobalt chloride hexahydrate, ammonium molybdate tetrahydrate, and thiourea as raw materials, stirring and mixing them evenly, and then performing a hydrothermal reaction. The product is subjected to a post-treatment process to obtain a Co-doped MoS2 catalyst;
[0009] Step 2: Co-doped MoS2 catalyst, conductive carbon black, anion exchange liquid, polyethylene glycol, anhydrous ethanol and deionized water are mixed and ultrasonically crushed to form a uniform slurry;
[0010] Step 3: Load the slurry onto the anion exchange membrane by spraying, and spray Pt / C on the other side.
[0011] Furthermore, in step 1, the molar ratio of the cobalt chloride hexahydrate, ammonium molybdate tetrahydrate and thiourea is 0.4-0.6:0.4-0.6:10-14.
[0012] Furthermore, in step 1, the temperature of the hydrothermal reaction is 190-210° C., and the time is 16-20 h.
[0013] Furthermore, in step 1, the post-treatment process is specifically as follows: washing with deionized water and anhydrous ethanol in sequence, centrifuging, and finally drying in a vacuum drying oven at 60-70° C. for 1-3 hours.
[0014] Furthermore, in step 2, the mass ratio of the Co-doped MoS2 catalyst, conductive carbon black, anion exchange liquid and polyethylene glycol is 15-20:4-6:90-110:25-35.
[0015] Furthermore, in step 2, the volume ratio of anhydrous ethanol to deionized water is 3-4:1-2.
[0016] Furthermore, in step 2, the frequency of the ultrasound is 80-100 kHz, and the time is 20-40 minutes.
[0017] Furthermore, in step three, the model of the anion exchange membrane is PiperIOn-A80-HCO3.
[0018] (3) Beneficial technical effects
[0019] (1) The present invention has a relatively loose requirement on temperature, and the hydrothermal synthesis conditions are mild, easy to control, and simple to operate. The nanoflower structure of the product is maintained during the synthesis process.
[0020] (2) The raw material cost used in the present invention is relatively low, thus avoiding the large-scale use of precious metals.
[0021] (3) The membrane electrode processing technology of the present invention is simple, and the catalyst is not easy to fall off during use. This method is suitable for mass production and has greater application potential in commercial water electrolysis materials. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0023] Figure 1 The scanning electron microscope image and corresponding mapping image of the Co-doped MoS2 catalyst in Example 1;
[0024] Figure 2 TEM image of the Co-doped MoS2 catalyst in Example 1;
[0025] Figure 3 This is the polarization curve of the Co-doped MoS2 catalyst in the three-electrode system in Example 1;
[0026] Figure 4 For Pt / C||Co-MoS2 in Example 1 at 1A / cm 2 Ut curve under constant current density;
[0027] Figure 5 X-ray diffraction patterns of the Co-doped MoS2 catalyst in Example 1 and the MoS2 catalyst in Comparative Example 1;
[0028] Figure 6 The scanning electron microscope image and corresponding mapping image of the MoS2 catalyst in Example 1;
[0029] Figure 7 1 is a transmission electron micrograph of the MoS2 catalyst in Comparative Example 1;
[0030] Figure 8 1 is a Raman spectrum of the Co-doped MoS2 catalyst in Example 1 and the MoS2 catalyst in Comparative Example 1;
[0031] Figure 9 Mo3d X-ray photoelectron spectra of the Co-doped MoS2 catalyst in Example 1 and the MoS2 catalyst in Example 1;
[0032] Figure 10 The S2p X-ray photoelectron spectra of the Co-doped MoS2 catalyst and the MoS2 catalyst in Example 1 are shown;
[0033] Figure 11 is the polarization curve of the MoS2 catalyst in the three-electrode system in Comparative Example 1;
[0034] Figure 121 is a Tafel slope plot of the Co-doped MoS2 catalyst in Example 1 and the MoS2 catalyst in Comparative Example 1;
[0035] Figure 13 2 are the resistance diagrams of the Co-doped MoS2 catalyst in Example 1 and the MoS2 catalyst in Comparative Example 1;
[0036] Figure 14 Polarization curves of Pt / C||Co-MoS2 in Example 1 and Pt / C||Co-MoS2 in Comparative Example 1 used in anion exchange membrane electrolyzers;
[0037] Figure 15 2 is a resistance diagram of Pt / C||Co-MoS2 used for anion exchange membrane in Example 1 and Pt / C||Co-MoS2 in Comparative Example 1. DETAILED DESCRIPTION
[0038] To facilitate understanding of the present invention, the present invention will be described in more detail below. Preferred embodiments of the present invention are provided below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present invention.
[0039] Example 1
[0040] A method for preparing an anion exchange membrane electrolyzer membrane electrode from transition metal sulfide Co-MoS2 comprises the following steps:
[0041] Step 1: Weigh 0.5 mmol of cobalt chloride hexahydrate, 0.5 mmol of ammonium molybdate tetrahydrate, and 12 mmol of thiourea as raw materials, add them into 30 mL of deionized water, stir and mix them evenly, and then carry out hydrothermal reaction at 200 ° C for 18 hours. The product is separated, washed with deionized water and anhydrous ethanol in turn, centrifuged, and finally dried in a vacuum drying oven at 60 ° C for 2 hours to obtain a Co-doped MoS2 catalyst;
[0042] Figure 1 The scanning electron microscope image and corresponding mapping image of the Co-doped MoS2 catalyst are shown in Figure 2. Figure 1 It can be seen that the synthesized Co-MoS2 has a nanoflower morphology, and the Co, Mo, and S elements are evenly distributed.
[0043] Figure 2 The transmission electron microscope image of the Co-doped MoS2 catalyst is shown in FIG. Figure 2 It can be seen that the lattice fringes corresponding to the Co-MoS2(002) and (100) planes correspond to Figure 1No additional Co compound related signals were observed in the XRD peaks at 14.36° and 32.61°, indicating that Co is an effective dopant to promote the electrochemical performance of MoS2.
[0044] Figure 3 is the polarization curve of the Co-doped MoS2 catalyst in the three-electrode system, Figure 9 It can be seen that the Co-doped MoS2 catalyst has a high conductivity of 10 mA / cm in alkaline OER. 2 The overpotential corresponding to the current density is 191mV, 100mA / cm 2 The overpotential corresponding to the current density is 310 mV.
[0045] Step 2: 20 mg of Co-doped MoS2 catalyst, 5 mg of conductive carbon black, 100 mg of anion exchange liquid, 30 mg of polyethylene glycol, 3.5 mL of anhydrous ethanol, and 1.5 mL of deionized water were mixed and ultrasonicated at an ultrasonic frequency of 100 kHz for 30 min to form a uniform slurry;
[0046] Step 3: Load the slurry onto the anion exchange membrane PiperIOn-A80-HCO3 by spraying, and spray Pt / C on the other side, controlling the spraying area to 2×2cm 2 , the loading amount is 4 mg / cm 2 , the membrane electrode can be obtained and named Pt / C||Co-MoS2.
[0047] Figure 4 For the Pt / C||Co-MoS2 at 1A / cm 2 Ut curve under constant current density.
[0048] Comparative Example 1
[0049] A method for preparing an anion exchange membrane electrolyzer membrane electrode from transition metal sulfide Co-MoS2 comprises the following steps:
[0050] Step 1: Weigh 0.5 mmol of ammonium molybdate tetrahydrate and 12 mmol of thiourea as raw materials, add them into 30 mL of deionized water, stir and mix evenly, carry out hydrothermal reaction at 200 ° C for 18 hours, separate the product, wash it with deionized water and anhydrous ethanol in turn, centrifuge it, and finally dry it in a vacuum drying oven at 60 ° C for 2 hours to obtain MoS2 catalyst;
[0051] Figure 5 The X-ray diffraction patterns of the Co-doped MoS2 catalyst and the MoS2 catalyst in Example 1 are shown in FIG. Figure 1It can be observed that the diffraction peaks of the Co-doped MoS2 catalyst in Example 1 correspond well to the MoS2 standard card, and no additional XRD signals appear.
[0052] Figure 6 The scanning electron microscope image and corresponding mapping image of the MoS2 catalyst show that the MoS2 catalyst has a nanoflower morphology, and the Mo and S elements are evenly distributed.
[0053] Figure 7 is a transmission electron microscope image of the MoS2 catalyst. Figure 7 It can be seen that MoS2 has (002) and (100) crystal planes. Compared with the Co-doped MoS2 catalyst, the addition of Co does not significantly change the lattice spacing of MoS2.
[0054] Figure 8 The Raman spectra of the Co-doped MoS2 catalyst and the MoS2 catalyst in Example 1 are shown in FIG. Figure 8 It can be seen that the incorporation of Co causes the Raman peak of Co-doped MoS2 catalyst to be slightly red-shifted compared with that of MoS2 catalyst.
[0055] Figure 9 The Mo 3d X-ray photoelectron spectra of the Co-doped MoS2 catalyst and the MoS2 catalyst in Example 1 are shown in FIG. Figure 9 It can be seen that compared with the MoS2 catalyst, the incorporation of Co causes Mo 3d to move to a higher binding energy, reducing the electron density of Mo, which is more conducive to the adsorption of *OO- and enhances the OER activity of Co-MoS2.
[0056] Figure 10 is the S2p X-ray photoelectron spectrum of the Co-doped MoS2 catalyst and the MoS2 catalyst in Example 1, Figure 10 It can be seen that the incorporation of Co causes the peak of S2p to shift, indicating a strong interaction between Co and MoS2. The incorporation of Co optimizes the electronic structure of MoS2, making it more conducive to the adsorption of intermediates during the reaction process.
[0057] Figure 11 is the polarization curve diagram of the three-electrode system of the MoS2 catalyst, Figure 11 It can be seen that MoS2 has a high conductivity of 10 mA / cm in alkaline OER. 2 The corresponding overpotential is 393mV, 100mA / cm 2 The corresponding overpotential is 671 mV, which is lower than the performance of the Co-doped MoS2 catalyst in Example 1.
[0058] Figure 12is the Tafel slope diagram of the Co-doped MoS2 catalyst and the MoS2 catalyst in Example 1, Figure 12 It can be seen that the Tafel slope of the MoS2 catalyst in alkaline OER is 233.78 mV dec-1, which is higher than that of the Co-doped MoS2 catalyst, indicating that the Co-doped MoS2 catalyst has higher catalytic kinetics.
[0059] Figure 13 The resistance diagram of the Co-doped MoS2 catalyst and the MoS2 catalyst in Example 1 is shown in FIG. Figure 13 It can be seen that the ohmic resistance of the MoS2 catalyst in alkaline OER is 1.86Ω, indicating that the electrical conductivity of the MoS2 catalyst is lower than that of the Co-doped MoS2 catalyst.
[0060] Step 2: Mix 20 mg of MoS2 catalyst, 5 mg of conductive carbon black, 100 mg of anion exchange liquid, 30 mg of polyethylene glycol, 3.5 mL of anhydrous ethanol, and 1.5 mL of deionized water, and ultrasonicate at a frequency of 100 kHz for 20-40 min to form a uniform slurry;
[0061] Step 3: Load the slurry onto the anion exchange membrane PiperIOn-A80-HCO3 by spraying, and spray Pt / C on the other side, controlling the spraying area to 2×2cm 2 , the loading amount is 4 mg / cm 2 , the membrane electrode can be obtained and named Pt / C||Co-MoS2.
[0062] Figure 14 The polarization curves of Pt / C||Co-MoS2 and the Pt / C||Co-MoS2 used in anion exchange membrane electrolyzer in Example 1 are shown in FIG. Figure 14 It can be seen that the Pt / C||MoS2 electrolyzer can only provide 0.54mA / cm at 2V. 2 The current density is much lower than that of Pt / C||Co-MoS2.
[0063] Figure 15 The resistance diagram of Pt / C||Co-MoS2 and the Pt / C||Co-MoS2 used for anion exchange membrane in Example 1 is shown in FIG. Figure 15 It can be seen that the ohmic resistance, polarization resistance and diffusion resistance of the Pt / C||Co-MoS2 electrolytic cell are lower than those of Pt / C||MoS2, so Pt / C||Co-MoS2 has higher water electrolysis performance.
[0064] Based on the ideal embodiments of the present invention, and with reference to the above description, relevant personnel can make various changes and modifications without departing from the technical scope of the present invention. The technical scope of the present invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.
Claims
1. A method for preparing anion exchange membrane electrolyzer membrane electrode from transition metal sulfide Co-MoS2, characterized in that: The following steps are involved: Step 1: Using cobalt chloride hexahydrate, ammonium molybdate tetrahydrate, and thiourea as raw materials, stirring and mixing them evenly, and then performing a hydrothermal reaction. The product is subjected to a post-treatment process to obtain a Co-doped MoS2 catalyst; Step 2: Co-doped MoS2 catalyst, conductive carbon black, anion exchange liquid, polyethylene glycol, anhydrous ethanol and deionized water are mixed and ultrasonically crushed to form a uniform slurry; Step 3: Load the slurry onto the anion exchange membrane by spraying, and spray Pt / C on the other side.
2. The method for preparing an anion exchange membrane electrolyzer membrane electrode from a transition metal sulfide Co-MoS2 according to claim 1, characterized in that: In step 1, the molar ratio of cobalt chloride hexahydrate, ammonium molybdate tetrahydrate and thiourea is 0.4-0.6:0.4-0.6:10-14.
3. The method for preparing an anion exchange membrane electrolyzer membrane electrode from a transition metal sulfide Co-MoS2 according to claim 1, characterized in that: In step 1, the temperature of the hydrothermal reaction is 190-210° C., and the time is 16-20 h.
4. The method for preparing an anion exchange membrane electrolyzer membrane electrode from a transition metal sulfide Co-MoS2 according to claim 1, characterized in that: In step 1, the post-treatment process is specifically as follows: washing with deionized water and anhydrous ethanol in sequence, centrifuging, and finally drying in a vacuum drying oven at 60-70° C. for 1-3 hours.
5. The method for preparing an anion exchange membrane electrolyzer membrane electrode from a transition metal sulfide Co-MoS2 according to claim 1, characterized in that: In step 2, the mass ratio of the Co-doped MoS2 catalyst, conductive carbon black, anion exchange liquid and polyethylene glycol is 15-20:4-6:90-110:25-35.
6. The method for preparing anion exchange membrane electrolyzer membrane electrode from a transition metal sulfide Co-MoS2 according to claim 1, characterized in that: In step 2, the volume ratio of anhydrous ethanol to deionized water is 3-4:1-2.
7. The method for preparing anion exchange membrane electrolyzer membrane electrode using a transition metal sulfide Co-MoS2 according to claim 1, characterized in that: In step 2, the frequency of the ultrasound is 80-100 kHz, and the time is 20-40 minutes.
8. The method for preparing anion exchange membrane electrolyzer membrane electrode using transition metal sulfide Co-MoS2 according to claim 1, characterized in that: In step 3, the model of the anion exchange membrane is PiperIOn-A80-HCO3.