Understanding surface structures of In2O3 catalysts during CO2 hydrogenation reaction using time-resolved IR, XPS with in situ treatment, and DFT calculations

•In situ calibrated assignments to carbon and oxygen species of in situ IR and XPS.•Correlating the O 1 s bonding energies of In2O3 surface with both in situ XPS and DFT.•Reveal the surface structures of important O species on In2O3 for CO2 hydrogenation.•Formation of Ov does not induce new feature to O1s binding energy.•CO2 exposure induced carbonates formation on In2O3 replaces the original hydroxyl.