Easy three steps gC3N4 exfoliation for excellent photocatalytic activity – An in-depth comparison with conventional approaches

Producing an ultrathin nanostructure through exfoliation of carbon nitride (gC3N4) significantly enhances the photoactivity of the material. However, the influence of the exfoliation method on the properties and photocatalytic activity of gC3N4 nanosheets is still poorly understood. In this study, conventional methods such as thermal, chemical and ultrasonic exfoliation of gC3N4 nanosheets have been compared with a three-step exfoliation method. The three-step exfoliation strategy allows the control of the microstructure, light absorption property, morphology and visible light photoactivity of gC3N4 nanosheets. Products show a superior photocatalytic efficiency under simulated sunlight compared to gC3N4 nanosheets obtained with conventional exfoliation methods. Degradation kinetics of this material are also superior. gC3N4 nanosheets prepared by three-step exfoliation exhibit a high specific surface area, optimal band gap energy structure, higher electron density and more efficient charge separation than products of conventional exfoliation methods. This new three-step exfoliation strategy is an easy way for obtaining high performance gC3N4 nanosheets for water purification.