Regulating the photoluminescence of carbon dots via a green fluorine-doping-derived surface-state-controlling strategy

Abstract

Herein, we report a green surface-state-controlling strategy to achieve the regulation of the photoluminescence (PL) properties of carbon dots (CDs) via fluorine (F)-doping techniques. Two types of F-doped CDs with different F contents (FCDs1 and FCDs2) were prepared with o-phenylenediamine and its derivative as carbon precursors via different F-doping routes at room temperature. An obvious red-shift of PL for both the obtained CD products was achieved, due to the narrower band gap induced by F-doping. FCDs1 exhibits favorable solid-state PL behaviors due to the alleviated aggregation-induced quenching attributed to the element-dilution effect and the formation of hydrogen bonds, and is used for latent fingerprint identification with high resolution. FCDs2 with a high F content is characterized with a prominent red-shift of 70 nm and used as a powerful probe for the quantitative detection of cobalamin based on inner filter effects, giving a limit of detection of 0.15 μmol L⁻¹.