Boosting the photocatalytic hydrogen production performance of graphitic carbon nitride nanosheets by tailoring the cyano groups

Graphitic carbon nitride (g-C3N4) is a promising visible light responsive photocatalyst for solar hydrogen production. However, pristine g-C3N4 suffers from severe charge recombination, resulting in a poor photocatalytic activity. Herein, a facile KOH-assisted sealed heating process is designed to tailor the electronic structure of g-C3N4, leading to a significantly enhanced and stable photocatalytic hydrogen production rate of 225.1 mmol h(-1) using only 50 mg of the photocatalyst. An excellent apparent quantum efficiency of 16.82% is achieved at 420 nm. Systematic studies reveal that KOH-assisted sealed heating can generate more cyano groups onto the framework of g-C3N4, which can increase the charge carrier density and reduce the surface charge transfer resistance, promoting charge separation and transfer. The new findings demonstrated in this work provide a facile strategy for the design of low-cost and efficient photocatalyst for solar fuel production. (C) 2021 Elsevier Inc. All rights reserved.

Automated summary

The electronic structure of graphitic carbon nitride (g-C3N4) was tailored through a KOH-assisted sealed heating process, resulting in a significantly enhanced and stable photocatalytic hydrogen production rate and high apparent quantum efficiency. The introduction of more cyano groups during the heating process promoted charge separation and transfer, improving the photocatalytic performance.