Enhanced Photocatalytic Hydrogen Evolution of Carbon Quantum Dot Modified 1D Protonated Nanorods of Graphitic Carbon Nitride

1D protonated graphitic carbon nitride (HCN) are prepared through free-template chemical method and further modified with different amount of carbon quantum dots (CQDs) to afford new hybrids denoted as HCNC-x (x represents weight ratio of CQDs) for photocatalytic hydrogen evolution. The immobilization of CQDs onto HCN not only significantly improves the visible-light harvesting, but also prolongs the lifetime of charge carriers upon photoexcitation and suppresses the recombination of electron–hole pairs because of the intimate interface formed between the two components with opposite charges. As a result, the HCNC-0.50 show the highest photocatalytic hydrogen evolution rate of 382 μmol h^–1 g^–1 under visible light irritation, which was about 3-fold of pristine HCNC-0.0. Moreover, no decay of activity is observed for the HCNC-x hybrids that is recycled after 12 h photocatalytic reaction and then exposed to air for half a year.