Nickel ion detection by imidazole modified carbon dots.

Nickel ions (Ni2+) were detected by a new imidazole modified carbon dots (CDs) based on fluorescence quenching method. Structural characterization of CD-imidazole quantum dots were accomplished by transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR). Spectroscopic properties were characterized by ultraviolet absorption spectrum and fluorescence spectrum. Ni2+ concentration showed good linear relationship with fluorescence quenching efficiency in the range of 6-100 mM (R = 0.99) and the limit of detection (LOD) was 0.93 mM. Imidazole modified CDs have strong selectivity of Ni2+ compared with other metal ions in aqueous solution. These results demonstrated that the fluorescence sense platform based on imidazole modified CDs can be applied to Ni2+ detection in environment.