An efficient top-down approach for the fabrication of large-aspect-ratio g-C3N4 nanosheets with enhanced photocatalytic activities

Abstract

Graphitic carbon nitride (g-C₃N₄) nanosheets with large aspect ratios were fabricated from bulk g-C₃N₄ through an efficient top-down approach of moderate disintegration–exfoliation using diluted H₂SO₄ as an “efficient knife”. By prior disintegration in a diluted H₂SO₄ solution, the exfoliation of bulk g-C₃N₄ was effectively accelerated. The as-prepared g-C₃N₄ nanosheets possess a two-dimensional (2D) thin-layer structure with seven-atom thickness, a large lateral size of about 1 μm, and a high specific surface area of 80 m² g⁻¹. Compared with the bulk precursor, the g-C₃N₄ nanosheets showed much higher efficiency of photogenerated charge transfer and separation, and consequently exhibited enhanced photocatalytic activity toward hydrogen evolution and pollutant decomposition under both full-sunlight and visible-light irradiation.