Formic acid fuel cells offer exciting prospects for powering portable electronic and MEMS devices. Pd-based catalysts further improve the performance of direct formic acid fuel cells while reducing catalyst costs over Pt-based catalysts. This study investigates several Pd-based catalysts, both unsupported and carbon-supported, and compares the electrochemical results with results obtained in an operating fuel cell. Power densities of up to 260 mW cm(-2) were achieved in a fuel cell at 750 mA operating at 30 degrees C. Carbon-supported catalysts and addition of other metals, such as gold, show potential in further improving the performance of Pd-based catalysts. (c) 2005 Elsevier B.V. All rights reserved.