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

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. [Display omitted] •We successfully prepared BaTaO2N (BTON) oxynitride using the Ba2Bi3Ta2O11Cl (BBTOC) oxyhalide.•The porous nanosheet of BTON can promote the transfer of photogenerated carriers and provide more active sites.•The oxygen evolution of BTON porous nanosheet is 3 times higher than that of BTON prepared by solid state method.