ABO3 perovskite catalyst screening for chemical looping methane partial oxidation from descriptor-based microkinetic analysis

Abstract

DFT calculations and descriptor-based microkinetic analysis have been performed to screen ABO3 perovskite catalysts for methane partial oxidation. The scaling relations indicate the adsorption energies of H@O and CH3@B have the capability of representing the energetics of methane oxidation, and bulk oxygen vacancy formation energy is identified to be a better single descriptor of the kinetics. The resultant volcano-shaped plot shows the catalytic activity varies in the order LaMnO3 > LaFeO3 > LaCoO3 ≈ LaCrO3, which agrees with the experimental findings and thus validates our theoretical predications. By screening 667 combinations of A- and B-cations based on electron neutrality, structural tolerance factors, and experimental verification, 77 ABO3 have been identified to be stable. Of them, SrRuO3, SmRhO3, LaIrO3, NdRhO3, and BaOsO3 are located at the summit of the volcano, which also exhibit satisfactory CO selectivity and enhanced carbon resistance compared to LaFeO3, and may act as the oxygen carrier candidates.