Energy Band Alignment of BiVO₄ from Photoelectron Spectroscopy of Solid-state Interfaces

International audienceThe interface formation and energy-band alignment at interfaces between polycrystalline BiVO4 and high-work-function RuO2 and low-work-function Sn-doped In2O3 (indium tin oxide) have been studied using photoelectron spectroscopy with in situ thin-film deposition of the contact materials. The Schottky barrier heights for both contact films differ by 0.85 eV, which is smaller than the difference in work function and the differences observed for other semiconducting oxides, indicating a partial Fermi-level pinning. On the basis of the present results and the comparison with other photoelectrochemically active oxides, the differences of band alignment obtained from solid/electrolyte and from solid/solid interfaces, which can exhibit substantial differences, are discussed