Visible-light-responsive Photocatalyst Based on Nitrogen-doped Bulk Oxide YTaO4−xNy for Z-scheme Overall Water Splitting

Graphical A visible-light-responsive photocatalyst based on nitrogen-doped bulk oxide YTaO 4− x N y was synthesized and used as an H 2 evolution photocatalyst for Z-scheme overall water splitting coupling with the PtO x /WO 3 as the O 2 evolution photocatalyst and the I − /IO 3− as the shuttle ions. Nitrogen doping into oxide has been proved to be an effective strategy to extend visible-light utilization of oxides with layered or channeled structure, but it is shortage for the bulk oxides free of layered or channeled structure. Here, we report a novel nitrogen-doped bulk oxide (denoted as YTaO 4− x N y ) with good visible light response. As benefited from the strong hybridization of N 2 p and O 2 p electronic state according to the density functional theory (DFT) calculations, the band gap (3.6 eV) of YTaO 4 precursor was sharply narrowed to 2.4 eV on YTaO 4− x N y due to the obvious uplift of the valence band maximum (VBM). After decorated with the platinum cocatalyst, the Pt/YTaO 4− x N y was used as the H 2 -evolving photocatalyst for assembly of Z-scheme overall water splitting system by coupling with the PtO x /WO 3 as the oxygen evolution photocatalyst and using the I − /IO 3− as the shuttle ions. This work enriches the material database of nitrogen-doped oxide with wide visible light absorption and shows its promising application in solar-to-chemical conversion.