Preparation method and application of cerium-doped CoTeO3 nano-cluster catalyst
By preparing cerium-doped CoTeO3 nanoclusters, the problems of poor conductivity and low catalytic activity of traditional electrocatalytic materials were solved, achieving a highly efficient electrocatalytic oxygen evolution reaction. It has excellent conductivity and stability and is suitable for hydrogen production by water electrolysis.
Patent Information
- Application Number
- CN202511833969.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-08
- Publication Date
- 2026-01-16
AI Technical Summary
Traditional transition metal oxide electrocatalytic materials have poor conductivity, low catalyst activity, and slow reaction kinetics in the electrocatalytic oxygen evolution reaction. In addition, precious metal catalysts are expensive and scarce.
Rare earth element-doped transition metal telluride nanoclusters were prepared by a one-step chemical reduction method. Cerium-doped CoTeO3 nanoclusters were formed by reduction with NaBH4. The metallic properties of tellurium and the lattice oxygen oxidation mechanism (LOM) were used to improve conductivity and expose active sites, forming small-sized nanocluster structures.
It significantly improves the conductivity and reaction kinetics of the catalyst, reduces the reaction overpotential, and enhances catalytic activity and stability. It is suitable for hydrogen production by water electrolysis under high current density and has good prospects for industrial application.
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Figure CN121344666A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of chemical energy materials technology, and in particular to a method for preparing and applying a rare earth cerium-doped CoTeO3 nanocluster catalyst. Background Technology
[0002] Producing clean hydrogen fuel by electrolyzing water using renewable energy is a promising new energy utilization pathway. However, the efficiency of hydrogen production through water electrolysis is limited by the slow oxygen evolution reaction (OER) at the anode. Although traditional precious metal catalysts (such as RuO2 / IrO2) have excellent performance, their high cost and resource scarcity severely limit their large-scale application.
[0003] Transition metal oxide nanomaterials have shown promising applications in the electrocatalytic oxygen evolution reaction (OER), but their generally poor conductivity limits further improvements in catalytic activity. In contrast, tellurides, belonging to the same group as oxides, exhibit superior conductivity due to the significantly lower electronegativity of tellurium compared to oxygen, resulting in stronger covalent and metallic bonds with metals. This property facilitates rapid electron transport between the catalyst and reaction interface during electrocatalysis, thereby significantly improving reaction kinetics.
[0004] In the electrocatalytic oxygen evolution reaction (OER), two key reaction mechanisms exist: adsorption evolution (AEM) and lattice oxygen oxidation (LOM). The widely accepted AEM mechanism relies on the adsorption and transformation of reaction intermediates by metal active sites; however, a linear constraint exists between the adsorption energies of these intermediates, requiring a high overpotential to drive the reaction. In contrast, the LOM mechanism involves the direct formation of O-O bonds between the reaction intermediate and the catalyst's own lattice oxygen. This pathway overcomes the aforementioned linear constraint, significantly reducing the reaction overpotential. Therefore, developing advanced catalysts based on the LOM mechanism provides a new strategic direction for overcoming the performance bottlenecks of traditional catalysts and achieving highly efficient OER processes. Summary of the Invention
[0005] To address the problems of poor conductivity, low catalyst activity, and slow reaction kinetics in traditional transition metal oxide electrocatalytic materials, this invention aims to develop a rare earth element-doped transition metal telluride and apply it to the electrocatalytic oxygen evolution reaction.
[0006] In a first aspect, the present invention provides a method for preparing a cerium-doped CoTeO3 nanocluster catalyst, characterized by comprising the following steps: (1) Dissolve cobalt acetate and cerium chloride in deionized water to obtain a metal salt solution; (2) Under nitrogen protection, NaBH4 aqueous solution was added to Te powder and completely dissolved to obtain a colorless and transparent NaHTe solution; (3) Under nitrogen protection, NaHTe solution was added dropwise to metal salt solution while stirring. After the addition was completed, stirring was continued until the reaction was complete. After centrifugation, the product was collected, washed and dried to obtain cerium-doped CoTeO3 nanocluster catalyst.
[0007] Preferably, in step (1), the molar volume ratio of cobalt acetate, cerium chloride and deionized water is 0.2mM~0.8mM:0.05mM~0.5mM:50mL.
[0008] Preferably, in step (1), the molar volume ratio of cobalt acetate, cerium chloride and deionized water is 0.5 mM: 0.1 mM: 50 mL.
[0009] Preferably, in step (2), the concentration of the NaBH4 aqueous solution is 0.5~2 mmol / L, and the molar volume ratio of tellurium (Te) powder to NaBH4 aqueous solution is 0.5 mM~1.0 mM: 5 mL~15 mL.
[0010] Preferably, in step (2), the concentration of the NaBH4 aqueous solution is 1 mmol / L, and the molar volume ratio of tellurium (Te) powder to NaBH4 aqueous solution is 0.5 mM: 10 mL.
[0011] Preferably, in step (3), the dropping speed is 0.5~2 drops / s, the stirring speed is 800~1200 rpm, the centrifugation speed is 8000~11000 rpm, the cleaning method is to alternate between ethanol and water for 2~4 times, the drying temperature is 50~80℃, and the drying time is 10~20h.
[0012] Preferably, in step (3), the dropping speed is 1 drop / s, the stirring speed is 1000 rpm, the centrifugation speed is 10000 rpm, the cleaning method is to alternate between ethanol and water for 3 times, the drying temperature is 60℃, and the drying time is 12h.
[0013] Secondly, an application of a cerium-doped CoTeO3 nanocluster catalyst is provided, which is used in the electrocatalytic oxygen evolution reaction.
[0014] Compared with traditional methods, the innovative advantages of this invention are mainly reflected in the following aspects: (1) Simple and efficient preparation process: The present invention adopts a one-step chemical reduction method, using NaBH4 as a reducing agent to directly reduce metal ions to the target product. The process is simple, the reaction conditions are mild, and the product yield is high, with good reproducibility and scalability potential. (2) Excellent electrical conductivity and reaction kinetics: Tellurium has metal-like properties. Its metal-metal bonding and narrow band gap endow the material with excellent electronic conductivity. Due to the introduction of Te, the charge migration rate during the catalytic process is significantly accelerated, thereby reducing the reaction overpotential and improving the overall reaction kinetics.
[0015] (3) Sufficient exposure of active sites: The slow dropwise addition of NaHTe solution and rapid stirring facilitate the uniform and rapid formation of a large number of crystal nuclei, while effectively inhibiting excessive growth of crystal nuclei, ultimately forming a small nanocluster structure. The unique nanocluster structure can greatly increase the catalytic activity specific surface area, expose more active sites, and thus enhance the intrinsic activity of the catalyst.
[0016] (4) Synergistic effect of catalytic mechanism: The lattice oxygen oxidation mechanism (LOM) was successfully introduced into the electrocatalytic oxygen evolution reaction, which broke through the energy barrier limitation of the reaction intermediate in the traditional adsorption evolution mechanism (AEM) and significantly improved the catalytic activity.
[0017] (5) High activity and stability at high current density: When the cerium-doped CoTeO3 nanocluster catalyst prepared in this invention is applied to the oxygen evolution reaction (OER) in water electrolysis, it exhibits high catalytic activity and stability at high current density and has good prospects for industrial application.
[0018] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description
[0019] Figure 1 Ce prepared in Example 1 0.10 Transmission electron microscopy morphology of CoTeO3 (A: 5nm, B: 2nm); Figure 2 Ce prepared in Example 1 0.10 X-ray diffraction patterns of CoTeO3 and the comparative preparation; Figure 3 The graph shows a comparison of the OER catalytic performance of the cerium-doped CoTeO3 nanocluster catalysts prepared in Examples 1-4. Figure 4 This is a comparison chart of the OER catalytic performance of the catalyst prepared in Example 1 and the comparative example and the commercial catalyst; Figure 5 Ce prepared in Example 1 0.10 Results of long-term stability tests on CoTeO3 and CoTeO3 prepared in the comparative example. Detailed Implementation
[0020] The present invention will be further described below. It should be noted that this embodiment is based on the present technical solution and provides detailed implementation methods and specific operation processes, but the present invention is not limited to this embodiment.
[0021] Example 1 This embodiment provides a method for preparing a cerium-doped CoTeO3 nanocluster catalyst, including the following steps: (1) Dissolve 0.5 mM cobalt acetate (C4H6CoO4•4H2O) and 0.1 mM cerium chloride (CeCl3) in 50 mL of deionized water to obtain a metal salt solution; (2) Place 0.75 mM tellurium (Te) powder in a 25 mL round-bottom flask, and then add 10 mL of 1 mmol / L NaBH4 aqueous solution under a nitrogen protective atmosphere. After it is completely dissolved, a colorless and transparent NaHTe solution is obtained. (3) Freshly prepared NaHTe solution was added dropwise to the metal salt solution under a nitrogen atmosphere at a rate of 1 drop / s, with rapid stirring at 1000 rpm. After the addition was complete, stirring was continued for 1 hour until the reaction was complete. After the reaction was complete, the product was collected by centrifugation at 10000 rpm and washed three times with alternating ethanol and water. Then, it was dried in a vacuum oven at 60°C for 12 hours to obtain the cerium-doped CoTeO3 nanocluster catalyst, named Ce. 0.10 CoTeO3.
[0022] Example 2 This embodiment provides a method for preparing a cerium-doped CoTeO3 nanocluster catalyst, which differs from Example 1 in that the amount of cerium chloride used in step (1) is 0.05 mM. Everything else is the same as in Example 1. The obtained cerium-doped CoTeO3 nanocluster catalyst is named Ce. 0.05 CoTeO3.
[0023] Example 3 This embodiment provides a method for preparing a cerium-doped CoTeO3 nanocluster catalyst, which differs from Example 1 in that the amount of cerium chloride used in step (1) is 0.15 mM. Everything else is the same as in Example 1. The obtained cerium-doped CoTeO3 nanocluster catalyst is named Ce. 0.15 CoTeO3.
[0024] Example 4 This embodiment provides a method for preparing a cerium-doped CoTeO3 nanocluster catalyst, which differs from Example 1 in that the amount of cerium chloride used in step (1) is 0.50 mM. Everything else is the same as in Example 1. The obtained cerium-doped CoTeO3 nanocluster catalyst is named Ce. 0.50CoTeO3.
[0025] Comparative Example This comparative example provides a method for preparing a CoTeO3 nanocluster catalyst, which differs from Example 1 in that the amount of cerium chloride used in step (1) is 0. Everything else is the same as in Example 1. The catalyst obtained in this comparative example is named CoTeO3.
[0026] Application examples This application example provides an application of a cerium-doped CoTeO3 nanocluster catalyst. The cerium-doped CoTeO3 nanocluster catalysts prepared in Examples 1-4, the CoTeO3 nanocluster catalysts prepared in the comparative example, and the commercial catalyst IrO2 (Aladdin, Ir≥84.5%) were used in the electrocatalytic oxygen evolution reaction in a KOH electrolyte solution, where the electrolyte solution was 1M KOH.
[0027] Results Analysis Figure 1 Ce prepared in Example 1 0.10 Transmission electron microscopy (TEM) morphology of CoTeO3. From Figure 1 As can be seen from A, Ce 0.10 CoTeO3 exhibits a uniformly dispersed nanocluster structure with no obvious large nanoparticles. Figure 1 Further magnification of the high-resolution electron microscope image (B) reveals that the nanoclusters are extremely small in size. These small nanoclusters can greatly expose the reactive surface area, thereby improving performance.
[0028] Figure 2 Ce prepared in Example 1 0.10 X-ray diffraction patterns of CoTeO3 and the comparative preparation. From Figure 2 It can be seen that, compared with CoTeO3, Ce 0.10 The absence of obvious diffraction peaks in CoTeO3 indicates that Ce 0.10 The absence of crystals within CoTeO3 further confirms that Ce... 0.10 CoTeO3 has a nanocluster structure.
[0029] The comparison of the electrocatalytic oxygen evolution (OER) catalytic performance of each catalyst in the application examples is shown in the figure below. Figures 3-5 As shown in Table 1.
[0030] Table 1 Comparison of OER performance of various catalysts in application examples
[0031] Figure 3 This is a comparison of the OER catalytic performance of the cerium-doped CoTeO3 nanocluster catalysts prepared in Examples 1-4. Figure 3As can be seen from Table 1, in a 1M KOH electrolyte solution, compared with other catalysts, the Ce prepared in Example 1... 0.10 CoTeO3 at 500 mA / cm 2 and 1000 mA / cm 2 It exhibits the lowest overpotential at high current densities, at only 273 mV and 290 mV, demonstrating its excellent catalytic activity.
[0032] Figure 4 This is a comparison chart of the OER catalytic performance of the catalysts prepared in Example 1 and the comparative example, and the commercial catalyst. From... Figure 4 As can be seen from Table 1, the cerium-doped CoTeO3 nanocluster catalyst prepared in Example 1 of this invention exhibits a performance of 500 mA / cm². 2 and 1000mA / cm 2 The overpotentials at high current densities are only 273 mV and 290 mV, while the overpotentials of the CoTeO3 catalyst prepared in the comparative example and the commercial catalyst IrO2 under the same conditions are much higher than those of the catalyst in Example 1. The lower overpotential is beneficial to improving the reaction rate and reducing energy costs. The above results verify the important role of cerium doping in improving catalytic activity.
[0033] Figure 5 Ce prepared in Example 1 0.10 Long-term stability test results of CoTeO3 and the comparative CoTeO3 prepared in the example. Figure 5 It can be seen that the Ce prepared in Example 1 0.10 CoTeO3 at 500 mA / cm 2 Under high current density, it maintained excellent stability throughout the 230-hour stability test, while the CoTeO3 prepared in the comparative example maintained stability at 500 mA / cm². 2 Under high current density, the stability was maintained for only 40 hours, therefore the Ce prepared by the invention... 0.10 The stability of CoTeO3 is due to the fact that CoTeO3 is not doped with Ce.
[0034] The above test results fully demonstrate the excellent performance of this catalyst in high current density electrocatalytic oxygen evolution, providing possibilities for its further application in industrial-grade water electrolysis for hydrogen production.
[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions 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 a cerium-doped CoTe03 nanocluster catalyst, characterized in that, The method comprises the following steps: (1) dissolving cobalt acetate and cerium chloride in deionized water to obtain a metal salt solution; (2) under the protection of nitrogen, adding an aqueous solution of NaBH4 into Te powder, and after complete dissolution, obtaining a colorless and transparent NaHTe solution; (3) under the protection of nitrogen, adding the NaHTe solution into the metal salt solution drop by drop while stirring, continuing to stir until the reaction is complete after the addition is completed, collecting the product after centrifugation, and performing cleaning and drying to obtain a cerium-doped CoTeO3 nanocluster catalyst. 2.The preparation method and application of the cerium-doped CoTeO 3 nanocluster catalyst according to claim 1, characterized in that, In step (1), the molar volume ratio of cobalt acetate, cerium chloride and deionized water is 0.2 mM-0.8 mM: 0.05 mM-0.5 mM: 50 mL.
3. The preparation method and application of the cerium-doped CoTe03 nanocluster catalyst according to claim 1, characterized in that, In step (1), the molar volume ratio of cobalt acetate, cerium chloride and deionized water is 0.5 mM: 0.1 mM: 50 mL. 4.The preparation method and application of the cerium-doped CoTeO 3 nanocluster catalyst according to claim 1, characterized in that, In step (2), the concentration of the aqueous solution of NaBH4 is 0.5-2 mmol / L, and the molar volume ratio of tellurium (Te) powder to the aqueous solution of NaBH4 is 0.5 mM-1.0 mM: 5 mL-15 mL. 5.The preparation method and application of the cerium-doped CoTeO 3 nanocluster catalyst according to claim 1, characterized in that, In step (2), the concentration of the aqueous solution of NaBH4 is 1 mmol / L, and the molar volume ratio of tellurium (Te) powder to the aqueous solution of NaBH4 is 0.5 mM: 10 mL. 6.The preparation method and application of the cerium-doped CoTeO 3 nanocluster catalyst according to claim 1, characterized in that, In step (3), the addition speed is 0.5-2 drops / s, the stirring speed is 800-1200 rpm, the centrifugal speed is 8000-11000 rpm, the cleaning method is alternating cleaning with ethanol and water for 2-4 times, the drying temperature is 50-80℃, and the drying time is 10-20 h. 7.The preparation method and application of the cerium-doped CoTeO 3 nanocluster catalyst according to claim 1, characterized in that, In step (3), the addition speed is 1 drop / s, the stirring speed is 1000 rpm, the centrifugal speed is 10000 rpm, the cleaning method is alternating cleaning with ethanol and water for 3 times, the drying temperature is 60℃, and the drying time is 12 h.
8. Use of the cerium-doped CoTe03 nanocluster catalyst according to claim 1, characterized in that, The cerium-doped CoTeO3 nanocluster catalyst is used in an electrocatalytic oxygen evolution reaction.