How ionomer influences ink properties during the preparation of a catalyst layer for a proton exchange membrane fuel cell (PEMFC)

At the catalyst layers of a proton exchange membrane fuel cell (PEMFC), the key electrochemical reactions of a hydrogen powered vehicle take place, where hydrogen and oxygen are converted into electricity and water. Improvements at the catalyst layers to optimize the electrochemical reactions will directly result in an increased performance of the PEMFC system. The catalyst layers are made through mixing the catalyst (platinum on carbon) with an ionic polymer (ionomer) in an alcohol and water. This slurry (ink) is mixed, coated as a thin layer, and finally dried to give rise to the catalyst layer. Then the anode and cathode catalyst layers are pressed at an elevated temperature to the membrane, which gives rise to the final catalyst coated membrane (CCM). All the processing steps have a strong influence on the final catalyst layer structure and electrochemical performance. Especially, the state of the materials within the ink. Currently, the interaction of materials within the ink is unkwown. Therefore, using CV-SANS would be desired, so that the interactions between the materials within the ink can be understood, which will help to improve the electrochemistry of the PEM fuel cell.