Effect of Surface Roughness of Carbon Nanotube-based Catalyst Layer for Polymer Electrolyte Membrane Fuel Cell Performance

The effect of surface roughness of the catalyst layer (CL) based on carbon-nanotube (CNTs) in contact with polymer electrolyte membrane (PEM) in polymer electrolyte membrane fuel cell (PEMFC) was studied. The surface roughness of vacuum-filtrated CL sheets were evaluated using laser microscope and the surface of CL sheet contacting the filter membrane was found to be smoother compared to the surface exposed to the air. When a smoother surface of the CL sheet was laminated with PEM to fabricate membrane-electrode-assembly (MEA), power density of the single cell was 604.6 mW cm-2 at 80 °C under 100%R.H., which was greater than the MEA having a rougher CL surface (542.4 mW cm-2).