Simple one-pot, high-yield synthesis of 2D graphitic carbon nitride nanosheets for photocatalytic hydrogen production

Abstract

2-Dimensional (2D) graphitic carbon nitrate (g-C₃N₄) nanosheets are particularly interesting photocatalytic materials because of their large surface area and excellent photoelectric properties. However, it remains challenging to synthesize 2D g-C₃N₄ nanosheets with high yield and high activity simultaneously. In this work, a urea-assisted one-pot method was developed in which the decomposition of urea released NH₃ gas which exfoliated bulk g-C₃N₄ into thin nanosheets and generated pores and wrinkles on their surface. The product g-C₃N₄ nanosheets therefore possessed abundant surface active sites for interaction with reactants and showed enhanced light utilization efficiency, giving rise to their improved hydrogen production activity which was 3.36 times higher than that of their bulk counterpart. Importantly, the yield of g-C₃N₄ nanosheets using this method was almost doubled compared to a previously reported ammonium chloride (NH₄Cl) assisted method. Given that g-C₃N₄ nanosheets are building blocks for various photocatalysts, the current synthetic method which produces g-C₃N₄ nanosheets with high yield and high activity shall pave the way for high-performance photocatalytic applications such as hydrogen production and more.