Green synthesis of carbon dots from prawn shells for highly selective and sensitive detection of copper ions

A facile, economical and effective green method was developed for synthesis of fluorescent carbon dots (C-dots) from prawn shells. The results showed that these C-dots (with an average diameter of 4 nm) possess many excellent features such as to eliminate blue fluorescence under UV light (lambda = 365 nm), with high monodispersity, good stability, excellent water solubility and high quantum yield (9%). We further explored these C-dots as effective sensing probes for Cu2+ detection and found that they exhibit excellent selectivity and sensitivity toward Cu2+ with a low detection limit of 5 nM. We further demonstrated this novel sensing platform on Cu2+ ions analysis from seawater samples. This method is extremely rapid, low cost, ecofriendly, highly selective and sensitive for Cu2+ ions sensing from various sources of environment such as drinking water, river water and sea water. (C) 2015 Published by Elsevier B.V.