Engineering ultrathin oxygen-doped g-C3N4 nanosheet for boosted photoredox catalytic activity based on a facile thermal gas-shocking exfoliation effect

Graphitic carbon nitride (g-C3N4) is a promising star photocatalytic material due to features of non-toxic, inexpensive, and easy to prepare, but only exhibited poor performance by the high carrier recombination rate. In this work, engineering of 2D ultrathin and O doping into g-C3N4 was achieved by using thermal gas shocking effect induced via endogenous gases from the urea solution and C/N-steam reforming reaction. The experimental results revealed that the optimal sample exhibited the photo-degradation rates of tetracycline (TC) within 2 h were 87.2%, and the photocatalytic H(2 )evolution rate reached 6.21 mmol h(-1) g(-1). This overwhelming photocatalytic performance is attributed to following factors, including ultrathin thickness results in reduced charge transfer distance, larger specific surface area exposed more active reaction sites, and O doping forms electron-rich centers to promote carrier separation and negative shift of the conduction band for enhanced the reduction potential of photogenerated electrons. This study presents an effective strategy for preparing high active g-C3N4 photocatalysts with optimized modification.

Automated summary

Graphitic carbon nitride (g-C3N4) is a promising photocatalytic material, but suffers from poor performance due to high carrier recombination rate. In this study, the authors successfully engineered 2D ultrathin and O-doped g-C3N4 through thermal gas shocking effect and chemical reactions, resulting in a highly active photocatalyst with optimized modification.