A silver-doped graphite-like carbon coating and preparation method thereof

Abstract

The invention discloses a silver-doped graphite-like carbon coating and a preparation method thereof. The preparation method of the silver-doped graphite-like carbon coating comprises the following steps that (1), a substrate subjected to pretreatment is placed in a vacuum cavity containing a chromium target, a carbon target and a silver target for plasma cleaning; (2), a chromium buffer layer isdeposited on the substrate subjected to the treatment in the step (1) by adopting an ion plating process under the vacuum condition, wherein the chromium target is taken as an evaporation source, andargon is taken as the working gas; (3), the silver-doped graphite-like carbon coating is deposited on the chromium buffer layer obtained in the step (2) by adopting the ion plating process under the vacuum condition, wherein the carbon target and the silver target are taken as evaporation sources, and argon is taken as the working gas; and (4), the vacuum condition keeps unchanged, a heat treatment is carried out on the substrate subjected to the treatment in the step (3), and therefore silver in the graphite-like coating can form short silver wires on the interfaces of carbon clusters, and the silver in the graphite-like coating is agglomerated in the graphite-like coating under the heat treatment condition. According to the method, the spontaneous escape of the silver in the silver-dopedgraphite-like carbon coating can be inhibited.

Description

technical field [0001] The invention belongs to the technical field of metal surface treatment, in particular to a silver-doped graphite-like carbon coating without silver escaping to the surface and a preparation method thereof. Background technique [0002] Proton exchange membrane fuel cell (PEMFC) is considered as the terminal power of new energy vehicles due to its advantages of high conversion efficiency, no pollution, and fast start-up. However, because most of the traditional PEMFC bipolar plates are graphite plates with a single plate thickness of 2mm, it is difficult to meet the requirements of small volume and high energy density for automotive battery packs. Therefore, substituting a metal plate with a thickness of less than 0.5 mm for a graphite plate with a thickness of 2 mm is an effective way to reduce the volume of fuel cells for vehicles. However, due to the easy passivation of the surface of stainless steel, aluminum and other metals, the contact resistan...

AI Technical Summary

Problems solved by technology

Doping metallic silver can improve the conductivity of graphite-like coatings, but the method of improving conductivity by increasing the doping amount of silver in graphite-like carbon coatings is limited due to the spontaneous escape behavior of silver.