(2ej) Effect of CO2-Pretreatment on Reverse Water Gas Shift (rWGS) Using Ni-Doped CaTiO3/CaO

Reverse water-gas shift (rWGS) that converts CO₂ to CO is one of the most important parts in the CO₂ utilization to produce various CO₂-derived chemicals and hydrocarbon fuels. However, the rWGS is accompanied by undesired CH₄ formation over the catalysts due to the excessive hydrogenation of CO to CH₄. Here, Ni-doped CaTiO₃/CaO were developed and in-situ exsolved Ni was dispersed evenly throughout host CaTiO₃ perovskite. 100% CO selectivity can be achieved even at low temperatures and high H₂/CO₂ ratio because of strong metal support interaction (SMSI) between Ni and CaTiO3 and small Ni crystallite size. Moreover, CO₂ conversion can be enhanced by absorbing CO₂ as a formation of CaCO₃ prior to rWGS. During the rWGS, increase in CO₂ coverage by CO₃^2- spillover from CaCO₃ can increase CO₂ conversion.