CO2 Decomposition Using Activated Rh- and Ru-SrFeO3-delta for Cyclic Production of CO

Abstract

As global warming problem caused by greenhouse gas (GHG) emissions accelerates, many methods to remove carbon dioxide (CO2) have been proposed. In particular, CO2 decomposition has been developed for GHG emission reduction and CO2 upcycling. Our group previously reported on the results of efficient CO2 decomposition using SrFeO3-delta (perovskite-type metal oxide). According to the results of the isothermal test of SrFeO3-delta, reaction for a long time at high temperatures is necessary for effective CO2 decomposition, and this may lead to inefficient energy use. Therefore, in this study, Rh and Ru were impregnated as catalysts to SrFeO3-delta. As a result of CO2 decomposition using these catalysts, CO2 decomposition appeared at a low temperature of -200 degrees C. The maximum produced CO concentration was 3 times higher due to the spillover phenomenon of the precious metal catalysts. The cyclic tests showed catalyst stabilities of Rh-and Ru-SrFeO3-delta as well as the potential for continued and improved CO production. In additions, this study demonstrated that the decomposition of CO2 and the production of CO are performed by reverse Boudouard reactions as well as oxygen vacancies. It is expected that these results will contribute to GHG emission reduction.