Co, Fe, and Mn in La-perovskite oxides for low temperature thermochemical CO2 conversion

Perovskite oxides of the form ABO3 have shown substantial promise in reverse water gas shift chemical looping (RWGS-CL) process for low temperature thermochemical CO2 conversion to CO. Transition metals on the ‘B’ site of these perovskite oxides hold the key to tuning the material properties essential for efficient CO2 conversion. The role of Co, Fe and Mn in LaBO3 has been investigated through a combined theoretical and experimental approach. Intrinsic oxygen vacancy formation characteristics of these materials and the electronic charge distribution were explored via ab-initio density functional theory (DFT) simulations, while the microscale properties like crystallite size and CO2 conversion yield were probed experimentally. Through this multiscale study, the material properties that govern the stable and enhanced CO2 conversion phenomenon by Fe rich perovskites as opposed to Co and Mn rich phases are differentiated.