Ultrathin sulfur-doped holey carbon nitride nanosheets with superior photocatalytic hydrogen production from water.

Sulfur-doped holey carbon nitride nanosheets were facilely prepared through subtly controlling of thiocyanuric acid precursor, resulting into an apparent quantum yield of 10 % at 420 nm for hydrogen production from water. • Ultrathin sulfur-doped holey carbon nitride nanosheets were successfully prepared via self-templating approach. • Optimized S-CN(0.1) performed superior hydrogen evolution rate of 6225.4 μmol g−1 h−1 (λ> 420 nm), almost 45 times higher than the pristine bulk one. • An apparent quantum yield of 10 % at 420 nm was achieved for hydrogen production. • A reliable and universal method was developed to realize morphological evolution of graphitic carbon nitride with increasing reaction sites. Surface engineering is an efficient way to enhance photoabsorption, promote charge separation and boost photocatalysis. Herein, sulfur-doped holey g-C 3 N 4 nanosheets have been prepared through a universal self-templating approach with thiocyanuric acid as the single-precursor. By subtly controlling the feeding amount of precursor, the synthesized sulfur-doped holey g-C 3 N 4 nanosheets exhibit excellent visible-light driven photocatalytic hydrogen production activity. The optimized catalyst presents a hydrogen evolution rate of 6225.4 μmol g−1h−1, with an apparent quantum yield of 10 % at 420 nm. Comprehensive characterizations and theoretical calculations suggest that the enhanced photocatalysis is attributed to the synergy of the enlarged surface area, the negatively-shifted conduction band, and the narrowed bandgap due to sulfur-doping and ultra-thin two-dimensional topology. This work highlights the importance of controlling the precursor dosage and inducing sulfur doping into the polymer, providing a promising and reliable strategy to simultaneously regulate the nanostructural and electronic structure of g-C 3 N 4 for highly efficient photocatalysis. [ABSTRACT FROM AUTHOR]