XC-72 carbon blacks were steam-etched for different lengths of time and were then used as catalyst supports for polymer electrolyte fuel cells (PEFCs). Transmission electron microscopy (TEM) results show that the central parts of the XC-72 carbon black samples were more easily etched away. X-ray diffraction results show that the 002 and 30 peaks were initially sharp, but then broadened during the corrosion process, indicating that more graphitic components are in the steam etched carbon blacks. The electrochemically active surface area (ECSA) of the steam-etched carbon black samples remained above 60% after running for 45 h corrosion test, while for the pristine carbon black samples, the ECSA dropped down to below 50%. Both the polarization curve results and the TEM micrographs of the catalysts after corrosion show that the corrosion resistance increased significantly in the steam-etched samples. These results indicate that steam etching is a simple and efficient method to increase corrosion resistance for PEFC catalysts. (C) 2012 Elsevier Ltd. All rights reserved.