Template-Free One-Step Synthesis of g‑C3N4 Nanosheets with Simultaneous Porous Network and S‑Doping for Remarkable Visible-Light-Driven Hydrogen Evolution

Graphitic carbon nitride (g-C3N4) has been widely studied as a fascinating visible-light-response two-dimensional semiconductor photocatalyst. Nevertheless, the quantum yield of g-C3N4 is unsatisfactory due to the insufficient surface reactive sites and slow charge migration efficiency caused by grievous agglomeration and large grain size. Herein this obstacle is overcome through a facile eco-friendly strategy based on effects from a bubble template and nonmetal heteroatom doping of g-C3N4. This treatment not only restricts the agglomeration but also creates more surface active sites for reaction and more porous channels for charge carrier transfer. Well-amended g-C3N4 nanosheets with porous network and sulfur-doping were prepared with larger specific surface areas and faster electron–hole migration and separation capacity. The modified g-C3N4 nanosheets possessed a H2 evolution rate 5.3 and 3.8 times enhanced compare with bulk g-C3N4 (BCN) and S-doped g-C3N4 (CNS).