Synthesis and characterization of high efficient photoluminescent sunlight driven photocatalyst of N-Carbon Quantum Dots

A one-step simple, novel and efficient route for the preparation of N-doped carbon quantum dots (N-CQDs) has been established through the hydrothermal method, using diethylenetriamine (DETA) and citric acid (CA) as the surface passivation agent and carbon source, respectively. The as-prepared N-CQDs exhibit excellent photostability emission property and excitation-independent emission behavior with a high quantum yield up to 95%, which is the maximum value attained until now. As well as the Photoluminescence (PL) intensity of the obtained N-CQDs is pH independent over a range of 4-12 and their PL intensity retains unchanged even after several hours of UV excitation and over six months of storage, presenting an outstanding stability. Most importantly, the experimental results showed that N-CQDs have exceptional photocatalytic performance in the photodegradation of Methyl Blue (MB) under visible and natural sunlight by in situ photogenerated of H2O2 in reaction media. The improved photocatalytic performance of N-CQDs was attributed to the important role of N dopant into CQDs.