Human’s overdependence on the fossil fuels has led to the continual increase in the atmospheric CO2 concentration, resulting in severe environmental issues. For efficiently utilizing CO2, this paper proposes a cerium-modified oxygen carrier, as a strong electron donor, which realizes low-temperature CO2 splitting via a chemical looping-based reverse water-gas shift. Experimental results indicate that the resulting CO yield with applied 0.5CeO2-x∙Fe∙CaO oxygen carrier increases by 536 μmol∙min-1∙g-1, whose CO2 conversion is 4.26 times higher than that of Fe∙CaO at 700℃. Moreover, the oxygen carrier remains admirable redox durability after 100 CO2 splitting cycles. Characterizations (CO2-TPD-MS, in situ EPR, etc.) results show that the satisfied performance originates from the generation of more medium-strong basic sites and oxygen vacancies, synergistically promoting the adsorption of CO2 and lowering the energy barrier of C=O dissociation. In situ XAFS measurements further demonstrate the existence of Fe-O-Ce structure, which could be the nature to dominant the electron donation capability of the oxygen carriers. These findings provide valid strategies for the design and developing of new-generation oxygen carriers with strong reducing ability and satisfied redox stability.
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