Engineering morphology and nitrogen content on graphitic carbon nitrides for efficient solar to hydrogen conversion reaction

Semiconducting polymeric graphitic carbon nitride (g-C3N4; GCN) has emerged as low-cost and robust photocatalyst to convert solar to chemical energy. Unfortunately, the preparation of GCN is carried out via thermal polymerization of melamine, results the GCN with low specific surface area and poor charge separation efficiency. Herein, we report the synthesis of high-quality one-dimensional g-C3N4 nanobelts with rich amino groups and higher surface area by treating melamine precursors with hydrochloric acid and subsequent thermal polymerization reaction. The GCN nanobelts produced after optimizing the HCl treatment can effectively generate H2 evolution rate of 2912.6 & mu;mol/g/h, which is six times higher than that of bulk GCN obtained via direct thermal polymerization reaction without any treatment. Meanwhile, the quantum efficiency of 3.8% at 420 nm toward solar to hydrogen conversion was achieved, prominently surpassing the many g-C3N4 nanostructures. Such onedimensional g-C3N4 nanobelt semiconductors are predicted to hold great potential for solar energy conversion reactions.