Reactive Inorganic Vapor Deposition of Perovskite Oxynitride Films for Solar Energy Conversion

The synthesis of perovskite oxynitrides, which are promising photoanode candidates for solar energy conversion, is normally accomplished by high-temperature ammonolysis of oxides and carbonate precursors, thus making the deposition of their planar films onto conductive substrates challenging. Here, we proposed a facile strategy to prepare a series of perovskite oxynitride films. Taking SrTaO 2 N as a prototype, we prepared SrTaO 2 N films on Ta foils under NH 3 flow by utilizing the vaporized SrCl 2 /SrCO 3 eutectic salt. The SrTaO 2 N films exhibit solar water-splitting photocurrents of 3.0 mA cm -2 at 1.23 V vs. RHE (reversible hydrogen electrode), which increases by 270% compared to the highest photocurrent (1.1 mA cm -2 at 1.23 V vs. RHE) of SrTaO 2 N reported in the literature. This strategy may also be applied to directly prepare a series of perovskite oxynitride films on conductive substrates such as ATaO 2 N ( A = Ca , Ba ) and ANbO 2 N ( A = Sr , Ba ).