Enhancing photocatalytic water splitting over nitrogen-rich BaTaO₂N with Zr doping

Photocatalytic hydrogen production offers a promising solution for the energy crisis and environmental pollution, and the performance of the photocatalyst is crucial for enhancing the efficiency of hydrogen production. Achieving the intricate structure of metal-doped perovskite oxynitride as photocatalysts responsive to visible light continues to pose a significant challenge. BaTaO₂N demonstrates excellent hydrogen evolution activity under visible light irradiation, and its absorption edge exceeds 600 nm. In this study, a N-rich BaTaO₂N with Zr doping photocatalyst (1 wt% Zr) was successfully synthesized <i>via</i> a flux method, thereby enhancing its activity for photocatalytic water splitting. The apparent quantum efficiency (AQE) at 420 nm is measured to be 1.73%. Doping with Zr results in a narrower band gap in BaTaO₂N and extends the electron lifetime. N-rich BaTaO₂N significantly enhances the separation efficiency of photogenerated electrons and holes, thereby elevating the catalytic activity of the photocatalyst.