Computational Study of Indium Oxide Photoelectrodes

Using a combination of first-principles molecular dynamics simulations and electronic structure calculations, we characterize the atomistic structure and vibrational properties of a photocatalytic surface of In2O3, a promising photoelectrode for the production of hydrogen peroxide. We then investigate the surface in contact with water and show that the electronic states of In2O3 are appropriately positioned in energy to facilitate the two-electron water oxidation reaction (WOR) over the competing four-electron oxygen evolution reaction. We further propose that the use of strained thin films interfaced with water is beneficial in decreasing the optical gap of In2O3 and thus in utilizing a wider portion of the solar spectrum for the WOR.