Photoelectrochemical water oxidation of LaTaON2 under visible-light irradiation

Abstract Lanthanum tantalum oxynitride (LaTaON 2 ) powders were prepared by one-step flux method. LaTaON 2 photoanodes, which are fabricated by using LaTaON 2 powders, are found to exhibit photoelectrochemical activity for overall water splitting. The photocurrent for LaTaON 2 photoelectrodes was ca. 120 μA cm −2 at 1.5 V vs. reversible hydrogen electrode (RHE) in 1 M NaOH aqueous solutions (pH = 13.6) under AM 1.5 G simulated sunlight irradiation (100 mW cm −2 ). The photocurrent of LaTaON 2 photoelectrode from back-side illumination is much larger than that from front-side illumination, suggesting that the photoelectrochemical property is mainly limited by poor continuous electron transport in the bulk. Further efforts to ameliorate the electron transport in the bulk of LaTaON 2 photoelectrodes are expected to significantly improve their photoelectrochemical performance.