Preparation method and application of low-load Pd/hollow carbon sphere oxygen reduction electrocatalyst

Abstract

The preparation method comprises the following steps: carrying out self-assembly on a macromolecular template agent and a carbon source precursor in a hydrothermal process to synthesize a hollow polymer sphere; then, providing a simple and convenient double-solvent impregnation method for successfully loading PdCl4<2-> on the hollow polymer sphere; and finally, placing the reactant in a programmable atmosphere tube furnace for high-temperature carbonization at 500-900 DEG C to obtain a low-load Pd / hollow carbon sphere oxygen reduction electrocatalyst (Pd-HCS), which can serve as an efficient ORR electrocatalyst in an alkaline environment. The low-load Pd-HCS oxygen reduction electrocatalyst obtained by the method has a relatively high specific surface area, good conductivity and enough active sites, and shows relatively excellent oxygen reduction electrocatalytic performance, good stability and excellent methanol poisoning resistance activity. The preparation method is simple in process and low in cost, has certain universality, and has certain guiding significance for designing and developing a novel fuel cell cathode oxygen reduction electrocatalyst.

Description

technical field [0001] The invention belongs to the field of chemical energy materials, and in particular relates to the preparation of hollow carbon sphere-based oxygen reduction electrocatalysts, in particular to a low-load Pd / hollow carbon sphere oxygen reduction electrocatalyst used to catalyze the reduction of oxygen at the cathode of a fuel cell into water. Preparation method and application. Background technique [0002] In recent years, due to the depletion of traditional fossil energy sources and the increasing environmental pollution, research and development of new efficient, low-cost and clean renewable energy conversion and storage technologies, such as fuel cells, zinc-air batteries, and water splitting, are highly desired. Among them, the fuel cell is developing the fastest and is considered as the energy star of the 21st century. It can directly convert the chemical energy in the fuel and oxidant into electrical energy without being limited by the Carnot cycl...

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Problems solved by technology

However, the preparation of the above-mentioned catalysts has the following problems: (1) Various carbon materials need to be pretreated, and additional amino groups are introduced to anchor the metal particles, thereby enhancing the force between the metal particles and the support and improving the dispersion of Pd nanoparticles (2) There is a certain phenomenon of particle agglomeration, and the preparation process is relatively cumbersome, time-consuming, and costly, and it is difficult to industrialize production

These problems are mainly due to the negatively charged noble metal ions (PtCl 4 2- , PdCl 4 2- ) exists, and there is an electrostatic repulsion between it and a large number of negatively charged oxygen-containing functional groups on the carbon precursor material, resulting in a certain agglomeration of the loaded noble metal nanoparticles

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