Methane-fueled thin film micro-solid oxide fuel cells with nanoporous palladium anodes

► Methane (CH4) was used to fuel thin film micro solid oxide fuel cells (μSOFCs). ► Pd was used as the μSOFC anode; while electrolytes and cathodes were 8 mol.% YSZ and Pt, respectively. ► Nanoporous Pd synthesized at high sputtering pressures when thickness was less than 56 nm. ► H2-fueled μSOFCs reached Pmax = 145 mW cm−2 and OCV = 1.03 V at 400 °C. ► CH4-fueled μSOFCs reached Pmax = 385 mW cm−2 and OCV = 0.77 V at 550 °C.