Hydrogen atom etching induced large-size ultrathin g-C3N4 nanosheets for enhanced photoluminescence

Large-size ultrathin g-C₃N₄ nanosheets have attracted extensive attention for their peculiar properties and promising practical application. Temporarily, g-C₃N₄ nanosheets are mostly obtained through thermal oxidation etching of bulk g-C₃N₄ which generally introduces defects including oxygen doping impurities. Here, we construct high-quality g-C₃N₄ nanosheets with thickness of about 2 nm and large lateral size up to 4 µm by hydrogen atom etching of bulk g-C₃N₄. The as constructed large-size ultrathin g-C₃N₄ nanosheets exhibit an enhanced photoluminescence with a quantum yield about two times that of the bulk g-C₃N₄. This work employs a facile method to prepare large-size g-C₃N₄, providing great guidance to the synthesis of other materials with similar structure.