Abstract
Direct methanol fuel cells (DMFCs) using Pt‐Ru electrocatalysts and perfluorosulfonic acid membranes provide high performances if operated above 100°C with optimized catalyst layers. A decal transfer method is used to apply thin‐film catalyst/ionomer composite layers to Nation® membranes. A Nation 112 membrane/electrode assembly operating on 5 atm oxygen at 130°C yields a current of 670 mA/cm2 at 0.5 V cell voltage. Peak power density is 400 mW/cm2. The same cell operating on 3 atm air at 110°C yields 370 mA/cm2 at 0.5 V and provides a maximum power density of 250 mW/cm2.