Preparation of Carbon Dots by PyrolyzingCarboxylate Ammonium Salt and its Application in Probing Ferric Ions

Abstract

In this paper, we have reported a novel and facile synthesis approach of fluorescent carbon dots (C-Dots) through a one-step pyrolytic route of carboxylate ammonium salt(formed between citric acid (CA) and N- (β-aminoethyl-γ-aminopropyl) methyl dimethoxysilane (AEAPMS)) without further passivation. The as-synthesized C-Dots possess excitation dependent fluorescence behaviors, strong blue photoluminescence (PL) emission with a quantum yield of 20.5% and pH stability. The morphology and structure of prepared C-Dots have been characterized by transmission electron microscope (TEM), X-ray diffraction (XRD) and Fourier transformed infrared spectroscopy (FTIR),TEMspectra reveal that the C-Dots arespherical nanoparticles with the size about 6.5 nm; FTIR indicate that there are lots of hydrophilic functional groups on C-Dots’ surface, which contribute to good water dispersibility. In addition, the obtained C-Dots exhibit a highly sensitive and selective fluorescence quenching effect toward Fe3+ ions in aqueous solution with a linear range of 0.05-0.20mM and a detection limit of 19.3 nM, which has great potential in environmental applications for Fe3+ detection.