Water splitting and CO2 reduction over an AgSr2Ta5O15 photocatalyst developed by a valence band control strategy

Abstract

Ag+ substitution was applied to a tungsten-bronze-type metal oxide. An AgSr2Ta5O15 photocatalyst has emerged for water splitting and CO2 reduction. DFT calculation and diffuse reflection spectra revealed that the Ag d-orbital formed a new valence band, leading to a narrow band gap (3.91 eV) compared to that of NaSr2Ta5O15 (4.11 eV).