Boosting photocatalytic hydrogen evolution rate over carbon nitride through tuning its crystallinity and its nitrogen composition.

The photocatalytic activity of graphitic carbon nitride (CN) is mainly restricted by its high recombination rate of charge carriers and narrow visible light absorption. In the present work, nitrogen-deficient CN (NDCCN) nanosheets with high crystallinity were synthesized using molten salt (NaLiCO) as an etching agent and high-temperature solvent. The electronic structure and energy band levels of the obtained NDCCN are optimized to extend its optical absorption and enhance separation efficiency of photo-generated charge carriers.