A Novel Visible-Light-Responsive Semiconductor ScTaO4−xNx for Photocatalytic Oxygen and Hydrogen Evolution Reactions

Graphical Photocatalysis : A nitrogen-doped tunable tunneled oxide ScTaO 4−x N x with an absorption edge of ca. 540 nm is identified as a narrow bandgap bifunctional photocatalyst for photocatalytic OER and HER. Screening of visible-light-responsive semiconductor photocatalysts is a significant target for solar water splitting systems. Herein, a newly designed Ta-based oxynitride, namely ScTaO 4−x N x , was successfully synthesized via nitrogen doping of ScTaO 4 oxide precursors at 1273 K under NH 3 flow. The ScTaO 4−x N x photocatalyst, with a strong band-to-band visible light absorption as far as 540 nm, can be employed for both water oxidation and reduction half-reactions under visible light illumination, demonstrating great potential for photocatalytic water splitting.