Optimization of alkaline catalytic inks for three-electrode electrochemical half-cell measurements

Recent development on new anionic exchange membranes for alkaline membrane fuel cells has led to an increase on electrocatalyst testing measurements in three-electrode half-cells in alkaline media. However, there is not yet any commercial alkaline ionomer widely used, comparing to Nafion® in acidic media. In this work, two different commercial alkaline ionomers (I2 from Acta and Fumion® FAA-3 from Fumatech) are tested. Different catalyst: ionomer ratios are employed in order to adjust the ink composition for a correct evaluation of the catalyst activity. For this purpose, a commercial 20 wt.% Pt/C catalyst was tested for CO electrooxidation and oxygen reduction reaction in thin layer RDE configuration.