The corrosion behaviour and electrochemical stability of two different electrocatalyst supports based on Sb-doped SnO2 (ATO) were evaluated in an acidic medium over a wide potential range (0-1.8 V vs. NHE). The results were compared with those from a commercial Vulcan carbon XC-72 (254 m(2) g(-1)) support. ATO (85 m(2) g(-1)) and modified-ATO (216 m(2) g(-1)) were synthesized by the sol-gel method and were then characterized by XRD, BET and TEM. The modification of the ATO consisted of adding dodecylamine as a surfactant to generate a surface area similar to that of Vulcan carbon. The electrochemical characterization conditions were chosen to match the operating conditions of a proton exchange membrane fuel cell (PEMFC) and a solid polymer electrolyser (SPE), where the oxygen-evolution reaction takes place at a potential near 1.6 V with respect to normal hydrogen electrode (NHE). The results show good chemical stability when the ATO and the modified-ATO are subjected to these conditions, whereas Vulcan carbon corrodes easily. This indicates that Sb-doped SnO2 is a good candidate for electrocatalyst supports for energy-conversion systems such as electrolysers and unified regenerative fuel cells. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.