Plasma-catalytic carbon dioxide conversion by reverse water–gas shift over La0.9Ce0.1B0.5B’0.5O3-δ perovskite-derived bimetallic catalysts

Reverse water–gas shift (RWGS) reaction is one of the most promising and feasible CO2 utilization strategy to generate CO, which together with renewable H2 could be employed for Fischer-Tropsch synthesis. In this study, RWGS over La0.9Ce0.1B0.5B’0.5O3-δ perovskite-derived bimetallic (Ni-Cu, Ni-Fe and Fe-Cu) catalysts as well as the corresponding Cu-, Ni- and Fe-based monometallic catalyst were investigated in a dielectric barrier discharge (DBD) plasma-catalysis system. The result demonstrated that the plasma-catalysis system is of great potential in promoting RWGS reaction at low temperature and atmospheric pressure. Among different catalysts, La0.9Ce0.1Ni0.5Cu0.5O3-δ (LCNCO) and La0.9Ce0.1Ni0.5Fe0.5O3-δ (LCNFO) exhibited higher catalytic performance in terms of CO2 conversion (27.3–53.7% for LCNCO and 26.8–51.4% for LCNFO) and CO selectivity (59.4–94.9% for LCNCO and 58.0–91.8% for LCNFO). Their superior performance should be attributed to the formation of Ni-(Cu, Fe) alloy with smaller particle size, which facilitated the activation of H2 and its spillover to nearby oxygen vacancies. In addition, the abundant oxygen vacancies of LCNCO and LCNFO provided sufficient active sites for CO2 adsorption, promoting the selective dissociation of CO2 to CO.