Synergetic effect of ZrO2 on the oxidation-reduction reaction of Fe2O3 during chemical looping combustion

► Properties of Fe2O3/ZrO2 composite. ► Adsorption of CO and O2 on Fe2O3/ZrO2 composite. ► Mechanisms of CO oxidation by Fe2O3 related to the fuel reactor of the CLC system. ► Mechanisms of Fe2O2 oxidation by O2 related to the air reactor of the CLC system.