Manufacturing porous BaTaO2N nanosheet via nitridation of a novel oxyhalide precursor for boosted photocatalytic water oxidation reaction

Abstract

BaTaO₂N (BTON) with a generous adsorption edge of ca. 660 nm and high theoretical solar-to-hydrogen conversion efficiency of ca. 20.6% has been extensively investigated for photocatalytic water splitting. In this study, we have successfully prepared a porous BTON nanosheet via employing Ba₂Bi₃Ta₂O₁₁Cl (BBTOC) oxyhalide as a novel nitridation precursor. The oxygen evolution rate of the BTON nanosheet is 108 μmol·h⁻¹, which is three times higher than that of BTON (25.9 μmol·h⁻¹) prepared by conventional solid-state method. The successful construction of porous BTON nanosheet is due to the structural transformation of BBTOC nanosheet precursor and facile evaporation of Bi and Cl elements. The porous nanosheet morphology of BTON can not only promote the transfer of photogenerated charge carriers but also provide abundant reaction sites for the oxygen evolution reaction. This work demonstrates a novel and efficient strategy for preparing oxynitride for efficient solar energy conversion.