Tuning the properties of luminescent nitrogen-doped carbon dots by reaction precursors

Four types of luminescent nitrogen-doped carbon dots (C-dots) are prepared by using glucose (G) or citric acid (C) as carbon source, and dopamine (D) or 4,7,10-trioxa-1,13-tridecanediamine (T) as nitrogen source, named GD-C-dots, GT-C-dots, CD-C-dots and CT-C-dots. The investigation on the optical, pH-sensitivity and photovoltaic properties of these C-dots illustrates that nitrogen source plays a key role in the properties of obtained C-dots. GD-C-dots and CD-C-dots show interesting electrochemical activities, which can provide fluorescent and electrochemical dual signals for practical applications. We demonstrate that not only the optical properties but also other physicochemical properties can be tuned by appropriate choice of the reaction precursors.