Photoelectrochemical oxidation of water using BaTaO2N photoanodes prepared by particle transfer method.

A photoanode of particulate BaTaO2N fabricated by the particle transfer method and modified with a Co cocatalyst generated a photocurrent of 4.2 mA cm(-2) at 1.2 V(RHE) in the photoelectrochemical water oxidation reaction under simulated sunlight (AM1.5G). The half-cell solar-to-hydrogen conversion efficiency (HC-STH) of the photoanode reached 0.7% at 1.0 V(RHE), which was an order of magnitude higher than the previously reported photoanode made from the same material. The faradaic efficiency for oxygen evolution from water was virtually 100% during the reaction for 6 h, attesting to the robustness of the oxynitride.