Promoted oxygen release from copper-ceria interfacial sites for selective hydrogen production

Abstract

The modulation of oxygen species is an effective strategy for selective H2 production with relevant chemical looping processes. This paper describes the promoted oxygen release from CuO-CeO2 redox catalysts for selective H2 production in chemical looping oxidative steam reforming of methanol (CL-OSRM). Despite the complete oxidation of methanol from CuO, the excess H2 production of CL-OSRM with respect to methanol steam reforming (MSR) increases linearly with the amount of active oxygen in CeO2 induced by the copper-ceria interaction. In situ spectroscopic characterizations and mechanistic study demonstrate that copper-ceria interfacial sites induce oxygen release from CeO2 to facilitate the partial oxidation of methoxy to formate species, which promotes the H2 production rate. This study provides an instructive strategy for the construction of redox catalysts for selective H2 production with chemical looping processes.