CN-116960375-B - Preparation of zero-dimensional/two-dimensional electrochemical dealloying PtCuBi/C electrocatalyst and application thereof in electrocatalytic oxidation of methanol

Abstract

The invention discloses a preparation method of a zero-dimensional/two-dimensional electrochemical dealloying PtCuBi/C electrocatalyst and application thereof in electrocatalytic oxidation of methanol. The invention adopts a simple solvothermal method and an electrochemical dealloying strategy to combine and prepare the 0D/2DD-PtCuBi/C electrocatalyst which can exist stably under the environmental condition. The unique 0D/2D mixed dimensional structure has rich atomic interfaces and larger specific surface, and the electrochemical dealloying method can be used for synthesizing the platinum-rich electrocatalyst by preferentially dissolving non-noble metals, so that the number of Pt active sites is obviously increased, and the catalytic performance of the electrocatalyst is improved. In addition, the introduction of the low-cost oxygen-philic metals Cu and Bi reduces the cost, and simultaneously, the 0D/2D D-PtCuBi/C electrocatalyst prepared by the invention has higher catalytic performance on methanol oxidation reaction compared with commercial Pt/C.

Inventors

• LI PENG
• LI SICHEN
• ZHOU XIAOXING
• Lu Maoni
• LI XINGHAO
• XIANG DONG
• SUN ZHENJIE

Assignees

• 安徽大学

Dates

Publication Date

20260512

Application Date

20230808

Claims (9)

1. 1. The preparation method of the zero-dimensional/two-dimensional electrochemical dealloying PtCuBi/C electrocatalyst is characterized by comprising the following steps: Step 1, taking acetylacetonate of Pt, hydrated chloride of Cu and nitrate of aerophilic metal Bi as alloy precursors, placing the alloy precursors and a certain amount of reducing agent in a reactor, adding solvent 1-octadecene and amine solution, and performing ultrasonic dissolution to form uniformly dispersed mixed solution; Step 2, heating the mixed solution obtained in the step 1 from room temperature to 150-190 ℃ and reacting for 5-60 minutes, naturally cooling to room temperature after the reaction is finished, washing with the ethanol and cyclohexane mixed solution, and centrifuging to obtain a black product; Step 3, placing active carbon into cyclohexane for ultrasonic dispersion, adding the black product obtained in the step 2 into the cyclohexane, continuing ultrasonic dispersion uniformly, washing and centrifuging with a mixed solution of acetic acid and ethanol, and drying to obtain a 0D/2D PtCuBi/C electrocatalyst; And 4, dispersing the 0D/2D PtCuBi/C electrocatalyst obtained in the step 3 in a mixed solution of ethanol and naphthol, carrying out ultrasonic treatment for 20min to obtain catalyst ink, transferring 5 mu L of catalyst ink onto a clean glassy carbon electrode, drying, scanning 100 circles in a saturated N 2 electrolyte of 0.1M HClO 4 at a scanning speed of 100mV/s, scanning the electric potential from 0.05V/RHE to 1.2V/RHE, and carrying out electrochemical dealloying to form the 0D/2D D-PtCuBi/C electrocatalyst.
2. 2. The method of manufacturing according to claim 1, characterized in that: In the step 1, the alloy precursors are Pt (acac) 2 、CuCl 2 ·2H 2 O and Bi (NO 3 ) 3 ·5H 2 O, wherein the molar ratio of Pt (acac) 2 、CuCl 2 ·2H 2 O to Bi (NO 3 ) 3 ·5H 2 O) is 5:10:1-10:1:10.
3. 3. The preparation method according to claim 2, characterized in that: In the alloy precursor, the mol ratio of Pt (acac) 2 、CuCl 2 ·2H 2 O、Bi(NO 3 ) 3 ·5H 2 O is 1:2:1.
4. 4. The method of manufacturing according to claim 1, characterized in that: In the step 1, the amine solution is oleylamine.
5. 5. The method of manufacturing according to claim 4, wherein: the volume ratio of the amine solution to the 1-octadecene is 3:2.
6. 6. The method of manufacturing according to claim 1, characterized in that: The reducing agent is glucose.
7. 7. The method of manufacturing according to claim 1, characterized in that: In the 0D/2D D-PtCuBi/C electrocatalyst, the Pt loading is 15% -20%.
8. 8. The application of the zero-dimensional/two-dimensional electrochemical dealloying PtCuBi/C electrocatalyst prepared by the preparation method of any one of claims 1 to 6, which is characterized in that: the zero-dimensional/two-dimensional electrochemical dealloying PtCuBi/C electrocatalyst is used as a high-efficiency electrocatalyst in the methanol electrocatalytic oxidation process under alkaline conditions.
9. 9. The use according to claim 8, characterized in that: The standard three-electrode system is used, a glassy carbon electrode with a zero-dimensional/two-dimensional electrochemical dealloying PtCuBi/C electrocatalyst is used as a working electrode, a platinum sheet electrode is used as a counter electrode, an Hg/HgO electrode is used as a reference electrode, and catalytic oxidation of methanol is carried out in alkaline electrolyte.

Description

Preparation of zero-dimensional/two-dimensional electrochemical dealloying PtCuBi/C electrocatalyst and application thereof in electrocatalytic oxidation of methanol Technical Field The invention belongs to the field of electrocatalytic of fuel cells, and particularly relates to preparation of a zero-dimensional/two-dimensional electrochemical dealloying PtCuBi/C electrocatalyst and application thereof in electrocatalytic oxidation of methanol. Background With the continual escalation of environmental problems and the reduction of fossil fuel reserves, the use of fuel cells as a clean energy source has received considerable attention. Direct Methanol Fuel Cells (DMFCs) play an important role in relieving environmental pollution and energy crisis problems due to the characteristics of high energy density, convenient storage and transportation, simple structure, environmental friendliness and the like. However, the slow kinetic rate and high cost of current Methanol Oxidation Reaction (MOR) catalysts have significantly hampered the large-scale commercial application of DMFCs. While platinum (Pt) based materials are widely considered one of the most prevalent catalysts for MOR, platinum (Pt) based materials face limitations in large scale applications due to the scarcity of resources, high cost and susceptibility to poisoning by carbonaceous intermediates (particularly CO ads). Thus, it remains a great challenge to find an effective method to manufacture a highly efficient platinum-based catalyst for MOR. Alloying the noble metal platinum with earth-rich non-noble metals can effectively improve electrocatalytic performance and solve the above-mentioned problems. This is because the alloy can promote the reduction of d-band center displacement, improve the surface electron environment, and facilitate the improvement of electrocatalytic performance. The existence of the low-cost aerophilic metals Cu and Bi can promote the adsorption of OH ads and accelerate the elimination of toxic intermediates, thereby further improving the efficiency of MOR. In order to enhance electrocatalytic activity and maximize the utilization of platinum atoms, researchers are currently focusing on creating unique microstructures that combine various advantages. For example, du et al achieved excellent ethanol and ethylene glycol oxidation electrocatalytic performance by designing the PdPt (JColloidInterface Sci 2022,610,271-279) catalyst with a unique 0D-2D composite structure. Wang et al assembled the ordered nanopolyhedron-nanowire-nanopolyhedron to prepare a hybrid dimensional Pt-Ni alloy polyhedral nano-chain (AdvMater 2023,35 (2), 2206508) as a dual-function electrocatalyst of the DMFC, effectively reducing the size effect. Their work provides a new strategy for synthesizing compounds with unique spatial structures that will promote their application in catalytic reactions. Electrochemical dealloying is a strategic method for synthesizing platinum-rich electrocatalysts by preferentially dissolving non-noble metals. The method is widely used in the design of ORR electrocatalyst because of the advantages of easy control, simple operation, low cost and the like. Straser and his colleagues successfully synthesized Pt-rich layer PtCu catalysts by electrochemical dealloying, showing very high ORR catalytic activity (j.am. Chem. Soc.2007,129, 12624-12625). However, the studies of multimetal Pt-based alloy MOR electrocatalysts designed for electrochemical dealloying strategies are limited. Based on the problems, the design of the electrocatalyst with high activity, high toxicity resistance and low cost has important industrial application significance. Disclosure of Invention The invention aims to provide a preparation method of a zero-dimensional/two-dimensional electrochemical dealloying PtCuBi/C electrocatalyst and application thereof in electrocatalytic oxidation of methanol. The invention combines a simple solvothermal method and electrochemical dealloying, and the prepared 0D/2DD-PtCuBi/C electrocatalyst can exist stably under the environmental condition. The unique 0D/2D mixed dimensional structure has rich atomic interfaces and larger specific surface, and the electrochemical dealloying method can be used for synthesizing the platinum-rich electrocatalyst by preferentially dissolving non-noble metals, so that the number of Pt active sites is obviously increased, and the catalytic performance of the electrocatalyst is improved. In addition, the introduction of the low-cost oxygen-philic metals Cu and Bi reduces the cost, and simultaneously, the 0D/2D D-PtCuBi/C electrocatalyst prepared by the invention has higher catalytic performance on methanol oxidation reaction compared with commercial Pt/C. The preparation method of the zero-dimensional/two-dimensional electrochemical dealloying PtCuBi/C electrocatalyst comprises the following steps: Step 1, taking acetylacetonate of Pt, hydrated chloride of Cu and nitrate of aerophilic metal