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

Here 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 content (FCDs1 and FCDs2) are prepared with o-phenylenediamine and its derivative as carbon precursors via different F-doping routines at room temperature. Obvious redshift the PL for both the obtained CDs products are 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 contributed by the element-dilution effect and the formation of hydrogen-bond, and is used for latent fingerprint identification with high-resolution. FCDs2 with high F content is characterized with prominent red-shifted of 70 nm, and is used as powerful probe for the quantitative detection of cobalamin based on inner filter effect, giving a limit of detection of 0.15 μmol/L.