Carbon NanoDots for Selective Optical Cation Detection

摘要

In the present work, custom designed and synthesized carbon nanodots (C-dots) with cation selective functional organic ligands (carboxyl- or amino-functionalized C-dots) are used for the optical detection of metal ions. These C-dots are highly uniform spherical shaped with a narrow size distribution, and high fluorescent efficiency. The ligands on the surface are able to provide the capping for the C-dots, while at the same time interact selectively with positively charged ions. Controlled experiments with carboxylated and aminated C-dots suggest that the fluorescence of these materials is highly dependent on the electrical field generated on their surface from the selective interaction of the charge ions with the functional sites of the C-dots. This charge can be developed selectively using different functionalities with different binding constants to monovalent and divalent metal ions. This allows for the selective optical detection using functionalized C-dots.