The Ce1-xLaxO2-delta solid solution (CL) supported Ir (nIr/CL, n = 2, 5 and 10 wt.%) catalysts are studied for H-2 production from ethanol oxidative steam reforming (OSR). The Ir dispersion, surface area, oxygen vacancy density and carbon deposition resistance of nIr/CL catalysts are greatly enhanced compared with Ir/CeO2. Among the tested catalysts, 5%Ir/CL shows the best catalytic performance, exhibiting >99.9% ethanol conversion at 400 degrees C with H-2 yield rate of 323 mu mol.g(cata)(-1).s(-1) and no obvious carbon deposition after used. The 5%Ir/CL catalyst contains the highest amount of reducible interface Ce4+, leading to a strong interaction with surface Ir species at the metal-support interface during the OSR reaction. The strong interaction induces Ir to be well dispersed on the CL support, and is associated with more redox-active sites (interface Ce4+/Ce3+), to guarantee high activity. (C) 2017 Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.