Highly sensitive fluorescent probe for selective detection of hypochlorite ions using nitrogen-fluorine co-doped carbon nanodots.

Hypochlorite ions (ClO) are widely used in bleaching agents and disinfectants. However, high concentrations of chloride species are harmful to human health. Therefore, effective methods for the detection of ClO ions are required. In this study, using 4-fluorophthalic acid and glycine, nitrogen-fluorine co-doped carbon nanodots (N,F-CDs) were synthesized by one-pot hydrothermal synthesis for use as a fluorescent probe for the fluorometric detection of ClO in aqueous media, based on the inhibition of n → π* transitions. The excitation and emission peak centers of the N,F-CDs are at 387 and 545 nm, respectively. The N,F-CDs show a fast quenching response (<1 min) for ClO and can be used in a wide pH range (pH 4-13). Under optimal conditions, the fluorescence intensity decreased with increase in the ClO concentration from 0 to 35 μM, and a low limit of detection (9.6 nM) was achieved. This probe possesses excellent selectivity and high sensitivity and was used to analyze standardized samples of piped water, achieving a satisfactory recovery. Thus, this nitrogen-fluorine co-doped nanodot probe is promising for the detection of pollutants.