The electronic structure of silver orthophosphate: experiment and theory

Abstract

Since the original discovery of the water-splitting activity of silver orthophosphate (Ag₃PO₄), considerable effort has been devoted to improving its photocatalytic activity and stability through morphology control and the design of multi-component electrode systems. Relatively little attention, however, has been paid to understanding the fundamental electronic properties of this material. Using X-ray photoelectron spectroscopy and hybrid density functional theory (DFT) calculations, we have studied the electronic structure of Ag₃PO₄. Our results indicate that hybrid DFT calculations closely reproduce the structural, electronic, and optical properties of Ag₃PO₄. From further analysis of the experimental and theoretical electronic structure data we have constructed a revised molecular orbital diagram for Ag₃PO₄ that highlights the strong covalent interactions formed in the tetrahedral PO₄ structural units.