The Influence of Polymeric Additives on the Structure of Catalytic Layers for the DMFC

摘要

The preparation of catalytic layers for the Direct Methanol Fuel Cell (DMFC) is not easy when highly reactive carbon supported metals are used as catalysts. When normal inks are applied in the thickness necessary to obtain a Platinum loading of 1-2 mg/cm~2 the layers tend to crack upon drying. Additives can be used to obtain more stable layers, but care must be taken not to reduce the electrochemical activity of the layers. We investigated the influence of additives on the electrochemical performance, the porosity and the microstructure of the layers. While the porosity data can explain partly, why additives reduce the catalytic activity of the layers, it is necessary to examine the structure on a submicrometer scale, to gain a better insight into the correlation between structure and performance.