Sustainable carbon dots as “turn-off” fluorescence sensor for highly sensitive Pb2+ detection
Carbon dots(C-dots) are a fascinating new class of fluorescent nanomaterials which gained attention ever since their accidental discovery by Xu. et al.  during the electrophoretic purification of single walled carbon nanotubes (SWCNTs) through arc-discharge method in 2004. They are characterized by exceptional tunable photoluminescent properties. C-dots are essentially carbon nanoparticles with nanocrystalline to amorphous sp2 cores having some form of surface passivation typically functionalized with complex surface groups, especially oxygen-related functional groups, such as carboxyl and hydroxyl [2, 3]. These surface groups make great contributions to the optical properties of C-dots and also make them aqueous dispersible. Due to their small particle size, C-dots possess strong quantum confinement and edge effects  due to which they exhibit photoluminescence which can be tailored by modifying surface or edges , doping and controlling the size . Besides,...
KeywordsC-dots Photoluminescence Pb2+ detection Fluorescence quenching
The authors gratefully acknowledge Sophisticated Analytical Instruments Facility (SAIF) at Sophisticated Test Instrumentation Centre (STIC), Cochin University of Science and Technology, Kerala for the support extended for HR-TEM imaging.
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