Cu2+ enhanced chemiluminescence of carbon dots-H2O2 system in alkaline solution.

Herein, Chemiluminescence (CL) behaviour of carbon dots (CDs) was investigated by using H2O2 as co-reactant in alkaline solution. The study demonstrated O2-, OH and 1O2 involved in the CL reaction processes. These reactive oxygen species reacted with CDs to produce CD•+ and CD•-, then the CD•+ reacted with CD•-to generate energy release in the form of CL emission. Importantly, we found that Cu2+ ion could greatly enhanced CL intensity (7.5 times) of CDs-H2O2 system, which was ascribed to Cu2+-catalysed H2O2 decomposition. Based on this system, the CL assay of ascorbic acid (AA) was developed. The limit of detection was as low as 0.03 μM, and the linear range was from 0.1 μM to 100 μM. The proposed method has been successfully utilized to determinate AA in beverage samples with satisfactory results.