Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Nishikyo-ku, Kyoto 615-8510, Japan.
CREST, Japan Science and Technology Agency (JST) , Kawaguchi, Saitama 332-0012, Japan.
J Am Chem Soc. 2016 Feb 24;138(7):2082-5. doi: 10.1021/jacs.5b11191. Epub 2016 Feb 15.
Mixed anion compounds are expected to be a photocatalyst for visible light-induced water splitting, but the available materials have been almost limited to oxynitrides. Here, we show that an oxychrolide Bi4NbO8Cl, a single layer Sillen-Aurivillius perovskite, is a stable and efficient O2-evolving photocatalyst under visible light, enabling a Z-scheme overall water splitting by coupling with a H2-evolving photocatalyst (Rh-doped SrTiO3). It is found that the valence band maximum of Bi4NbO8Cl is unusually high owing to highly dispersive O-2p orbitals (not Cl-3p orbitals), affording the narrow band gap and possibly the stability against water oxidation. This study suggests that a family of Sillen-Aurivillius perovskite oxyhalides is a promising system to allow a versatile band level tuning for establishing efficient and stable water-splitting under visible light.
混合阴离子化合物有望成为可见光诱导水分解的光催化剂，但可用的材料几乎仅限于氧氮化物。在这里，我们表明，一种氧氯化物 Bi4NbO8Cl，一种单层 Sillen-Aurivillius 钙钛矿，在可见光下是一种稳定且高效的 O2 析出光催化剂，通过与 H2 析出光催化剂（掺 Rh 的 SrTiO3）耦合实现 Z 型整体水分解。研究发现，由于高度分散的 O-2p 轨道（而不是 Cl-3p 轨道），Bi4NbO8Cl 的价带最大值异常高，从而产生了窄带隙，并且可能对水氧化具有稳定性。这项研究表明，Sillen-Aurivillius 钙钛矿卤氧化物家族是一个很有前途的体系，可以通过灵活的能带水平调谐来建立可见光下高效稳定的水分解。
