Fluorescence quenching mechanism of P-doped carbon quantum dots as fluorescent sensor for Cu2+ ions

Carbon quantum dots (CQDs), were gaining traction as promising optical detection materials due to its unique properties.In this research, rice stock is utilized as source of carbon and phosphorus is utilized as source of phosphorus to render phosphorus-doped carbon quantum dots.The P-CQDs may be generated in an economical and environmentally responsible manner using this technique.Under optimal conditions of temperature and pH, the synthesized green fluorescent P-CQDs were monodispersed and spherical in shape having an average size of 5.4 nm and a high quantum yield of 32.61%. Because of the interaction of P-CQDs and Cu2+ ions, the fluorescence properties of P-CQDs are quenched when they are in the presence of Cu2+ ions.With the incorporation of Cu2+ ions into P-CQDs, electron transport was enhanced, which may lead to fluorescence quenching, under optimal circumstances.According to the results of a spectroscopic analysis, Cu2+ ions can be detected at concentrations ranging from 0 to 260 μM, with a lower limit of detection of 0.032 μM.A real implementation of detecting Cu2+ in tap water was also carried out, and the results showed a satisfactory recovery rate. In a direct result of these, the implementation of a Cu2+ sensor may also be considered a real scenario.