Carbon nanodots sensitized chemiluminescence on peroxomonosulfate-sulfite-hydrochloric acid system and its analytical applications

In the present work, new water-soluble fluorescent carbon nanodots (C-dots) were prepared in a facile microwave pyrolysis approach in minutes by combining glycine and polyethylene glycol 200 (PEG 200). Transmission electron microscopy (TEM) measurements showed that the resulting C-dots had diameters of about 3 nm. C-13 NMR spectra further confirmed the presence of carbons (sp(2) and sp(3)) indicating a nanocrystalline core of the resulting C-dots with hydroxyl of PEG 200 covered outside. It was discovered that the prepared C-dots could dramatically enhance the chemiluminescence (CL) intensity of potassium peroxomonosulfate-sodium sulfite-hydrochloric acid (PSHA) reactions. UV-vis absorption and photoluminescence (PL) spectra indicated that the C-dots sensitized enhancements originated from their energy transfer and electron-transfer annihilation effects on the CL system. When the concentration of C-dots was 4 x 10(-5) M, and those of KHSO5, Na2SO3 and HCl were 1 x 10(-2) M, an excellent performance was obtained. The C-dots sensitized CL system was successfully applied to the determination of aliphatic primary amines in real water samples with satisfactory results. (C) 2012 Elsevier B.V. All rights reserved.