Gas diffusion electrodes for high temperature PEM-type fuel cells: role of a polymer binder and method of the catalyst layer deposition

The topic of this study is the optimization of the preparation procedure and chemical composition of a gas diffusion electrode (GDE) for utilization in high-temperature PEM fuel cells. A phosphoric acid-doped polybenzimidazole derivative membrane was used as a polymer electrolyte. The following parameters were studied: nature and content of the polymeric binder (PTFE-hydrophobic, PBI-hydrophilic) in the catalytic layer (CL) and concentration of platinum in catalytic powder (affecting the thickness of the CL). Brushing and spraying were selected as the most suitable techniques of CL deposition. Surprisingly, both polymeric binders investigated in the framework of this study were found to provide a similar GDE performance for CL deposited on the gas diffusion layer surface by spraying.