PRODUCTION OF A PLATINUM-FREE CHELATE CATALYST MATERIAL AS AN INTERMEDIATE PRODUCT, AND FURTHER PROCESSING THEREOF TO OBTAIN AN ELECTROCATALYTIC COATING AS A FINAL PRODUCT

摘要

Disclosed is a platinum-free chelate catalyst material which is used for a selective oxygen reduction in hydrogen fuel cells and methanol fuel cells, e.g. in the automobile industry. The porosity and the catalytic activity that can be obtained are not sufficient during the production for commercial purposes as a result of sintering effects occurring during a high-temperature treatment. The inventive method is therefore characterized by a low-temperature plasma treatment of the powdery transition metal chelate in a plasma reactor chamber with an inert plasma gas, the plasma performance, plasma gas pressure, plasma initialization, and treatment period being selected such that the molecules of the transition metal chelate are fragmented in the plasma and are crosslinked in a subsequent chemical reaction in such a way that the carbon matrix is embodied while the basic chelate structure remains intact in the surroundings of the transition metal. The obtained chelate catalyst particles are highly porous and have a size in the range of 0.06 ?m. The obtained intermediate product can be further processed by means of a combined sputter-plasma treatment using two different low-temperature plasmas which feature different performances and are operated in parallel or alternatingly so as to obtain an electrocatalytic coating as a final product, especially for use on a gas diffusion electrode.