Understanding the effect of Ag doping on methanol catalytic oxidation over CeCoOy mixed oxide catalysts

Abstract

Ag-doped Ce_1-xAg_xCoO_y mixed oxide catalysts were synthesized via the sol-gel method and applied to methanol catalytic oxidation. Ag doping induced the oxidation of Co²⁺ to Co³⁺ and weakened CoO bonds, thereby creating additional adsorption sites and enhancing surface-active oxygen species while lowering the reduction peak temperature. Ce_0.8Ag_0.2CoO_y catalyst achieved 99.6 % methanol conversion at 110 °C, mainly due to its abundant surface oxygen species and enhanced low-temperature redox capacity, which rapidly replenished the surface lattice oxygen consumed during methanol oxidation, thus facilitating efficient redox cycling.