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Conversion of CO 2 in a scalable technology has the potential for enormous energy and environmental impact but remains a challenge. We present several stable, earth abundant perovskite oxide materials for the reverse water gas shift chemical looping (RWGS-CL) process as a potential solution for this CO 2 mitigation problem. This material and process combination circumvents issues plaguing other emerging technologies, viz. poor rates of CO 2 conversion, high operation temperatures, use of precious metal catalysts, or combinations thereof. Using DFT-calculated oxygen vacancy formation energy, a key descriptor for the RWGS-CL process, we have successfully predicted several earth abundant perovskite oxides with high CO 2 conversion capability. We simultaneously achieved 100% selective CO generation from CO 2 at the highest known rates (∼160 μmoles per min per gram perovskite oxide) at record low process temperatures of 450–500 °C using lanthanum and calcium based perovskite oxides. These materials are stable over several RWGS-CL cycles, enabling industrial implementation. 

Current society is inherently based on liquid hydrocarbon fuel economies and seems to be so for the foreseeable future. Due to the low rates (photocatalysis) and high capital investments (solar-thermo-chemical cycles) of competing technologies, reverse water gas shift (rWGS) catalysis appears as the prominent technology for converting CO 2 to CO, which can then be converted via CO hydrogenation to a liquid fuel of choice (diesel, gasoline, and alcohols). This approach has the advantage of high rates, selectivity, and technological readiness, but requires renewable hydrogen generation from direct (photocatalysis) or indirect (electricity and electrolysis) sources. The goal of this review is to examine the literature on rWGS catalyst types, catalyst mechanisms, and the implications of their use CO 2 conversion processes in the future.