Preparation method of N/S-codoped carbon microspheres with high oxygen reduction catalytic activity

Abstract

The invention provides a preparation method of N / S-codoped carbon microspheres with high oxygen reduction catalytic activity. The preparation method comprises the following steps: adding a carbon source, a nitrogen source, a sulfur source and an analytically pure surfactant into a stainless steel reaction kettle in sequence under nitrogen protection, stirring, sealing, heating in a crucible furnace, and taking out a mixture when the reaction kettle is cooled naturally to room temperature; washing and filtering the mixture; drying obtained powder in a vacuum drying oven; uniformly mixing an obtained product with analytically pure potassium hydroxide powder, activating in an argon atmosphere; washing with distilled water; and finally, drying in vacuum in the vacuum drying oven. The preparation method has the advantages of simple process, mild reaction condition, high repeatability and low cost; in an alkaline environment, the generated product has excellent oxygen reduction catalytic property, is relatively high in catalytic activity, good in stability and relatively good in tolerance to methyl alcohol and carbon monoxide and has huge application potential on the aspect of fuel cell catalysts.

Description

technical field [0001] The invention relates to a preparation method of a fuel cell catalyst. Background technique [0002] With the development of society, human beings' demand for energy is increasing, and the energy crisis worldwide is gradually becoming prominent. As a clean, stable and efficient new energy source, fuel cells have been highly valued by people and are the focus of the new energy field. One of the directions of development. However, the energy conversion efficiency of fuel cells is severely constrained by the kinetics of the oxygen reduction reaction. Platinum and its alloys are by far the most efficient and widely used cathode catalysts for fuel cells. However, platinum-based catalysts also have some disadvantages that cannot be ignored. Platinum reserves are scarce in nature, so the cost has been high. In addition, platinum-based catalysts are less stable and less tolerant to carbon monoxide and methanol. These disadvantages greatly limit its practi...

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Problems solved by technology

However, the steps of these two preparation methods are relatively cumbersome, which is not conducive to large-scale synthesis

Qiu-Feng Lu et al. (Journal of Analytical and Applied Pyrolysis, 2012, 93: 147-152) obtained nitrogen-doped carbon hollow spheres by high-temperature pyrolysis of copolymers, and the material did not show electrochemical performance; Zheng Mingtao et al. (Acta Inorganic Chemistry, 2013, 29: 1391-1399) Using soluble starch as a carbon source, monodisperse sulfur-doped carbon microspheres with an average particle size of about 4 microns were prepared in one step by sulfur-assisted hydrothermal carbonization (550°C). However, the material did not exhibit electrochemical performance such as oxygen reduction catalysis.

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