Green synthesis of fluorescent carbon dots using chloroplast dispersions as precursors and application for Fe<sup>3+</sup> ion sensing
Yong Ran, Shao-Yu Wang, Qianye Yin, Aoli Wen, Xiaoxiao Peng, Yunfei Long, Shu Chen
Abstract
Abstract Water‐soluble carbon dots (CDs) were synthesized using a one‐step hydrothermal treatment of chloroplast dispersions extracted from fresh leaves as a green carbon source. The CD solution showed an emission peak centred at 445 nm when excited at 300 nm. The synthesized CDs were uniform and monodispersed with an average size of 5.6 nm. When adding ferric(III) ions (Fe 3+ ) to the solution of the original CDs, the fluorescence intensity decreased significantly. Based on the linear relationship between fluorescence intensity and concentration of Fe 3+ ions, an effective method for rapid, sensitive and selective Fe 3+ sensing in aqueous solution could be established. Under optimum conditions, the extent of the fluorescence quenching of prepared CDs strongly depended on the Fe 3+ ions over a wide concentration range 1.0–100.0 μM with a detection limit (3σ/k) of 0.3 μM. Furthermore, the quantitative determination of Fe 3+ ions in environmental water samples was realized.