Green Synthesized Luminescent Carbon Nanodots for the Sensing Application of Fe³⁺ Ions

A single step hydrothermal mode of carbon nanodots (C-dots) synthesis from house-hold kitchen garbage such as snake gourd peel extract was successfully carried out. Characterisation of green synthesized C-dots were accomplished using UV-Visible and FTIR spectroscopy, Spectrofluorimetry and HRTEM. C-dots exhibited an appreciable quantum yield of 28.6%. Excitation-dependent photoluminescence emission properties and pH-sensitivity of C-dots were also studied in detail. C-dots exhibited strikingly selective detection of Fe³⁺ ions via fluorescence quenching mechanism. Linearity was obtained in a concentration range of 10-100 μM with detection limit of 0.398 μM in accordance with the Stern-Volmer relation. The existence of oxygen containing functional moieties in luminescent C-dots could be attributed to the effectual complexation between the metal ion and C-dots. The selective sensing property of C-dots towards Fe³⁺ ions provide avenue for biochemical analysis related to iron metabolism and diagnosis of anaemia.