Flawless proton exchange membrane directly coated with catalyst as well as preparation method and application of flawless proton exchange membrane

Abstract

The invention relates to the technical field of fuel cell catalyst layer preparation, in particular to a flawless proton exchange membrane directly coated with a catalyst and a preparation method and application thereof. The preparation method comprises the following steps: mixing a perfluorosulfonic acid solution, normal propyl alcohol and deionized water to obtain dispersion liquid; wetting a catalyst with deionized water, then mixing the catalyst with the dispersion liquid, and carrying out ultrasonic dispersion treatment to form primary dispersion catalyst slurry; performing high-shear dispersion on the primary dispersed catalyst slurry to obtain secondary dispersed catalyst slurry; and finally, carrying out single-layer coating by adopting a blade coating process to obtain the flawless proton exchange membrane directly coated with the catalyst. Compared with the prior art, the fuel cell catalyst layer manufactured by the method is uniform in thickness, good in consistency and free of surface cracks, catalyst layers with different thicknesses can be manufactured according to different catalyst feeding amounts, and the method is suitable for production of domestic fuel cell membrane electrodes.

Description

technical field [0001] The invention relates to the technical field of fuel cell catalyst layer preparation, in particular to a flawless catalyst directly coated with a proton exchange membrane and its preparation method and application. Background technique [0002] During the electrochemical process of the cathode of the fuel cell, the oxygen in the air diffuses to the proton exchange membrane through the gas diffusion layer (GDL), and the hydrogen protons generated by the electrochemical reaction at the anode are transferred to the cathode through the proton exchange membrane. After the hydrogen protons and oxygen meet at the active sites on the surface of the noble metal catalyst, combined with the electrons transferred from the external circuit, an oxygen reduction reaction (ORR) occurs to generate water and heat at the same time. [0003] How to efficiently prepare membrane electrodes, the core components of fuel cells with excellent performance, is particularly import...

AI Technical Summary

Problems solved by technology

[0006] Most of the catalytic layers currently used have many problems: the coating process will be doped with air bubbles, the wet coating will appear in stripes or droplet lines, and the thickness of the wet coating will be uneven; after drying, large bumps or depressions will appear, and the catalytic layer will The thickness is uneven; there are obvious cracks in the catalytic layer after drying, etc.

These problems will not only affect the morphology of the catalytic layer, but also affect the diffusion and discharge of protons, electron transfer channels, gases, and water in the catalytic layer. For example, large cracks in the catalytic layer will cause proton transfer channels and electron transfer channels. It will cause a bypass for the diffusion of reaction gas and product water, which will affect the performance and life of the fuel cell

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