In this work, we found that Rh-Ni bimetallic nanocatalysts, with a rhodium content as low as 10 mol %, prepared by the coreduction of the corresponding metal chlorides, exhibit excellent catalytic activity to the decomposition of hydrous hydrazine, producing hydrogen with 100% selectivity at 323 K. The present catalyst with low noble-metal content promotes the practical use of the hydrogen-storage system based on the catalytic complete decomposition of hydrazine in aqueous solution at ambient conditions. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.