A novel water soluble chemosensor based on carboxyl functionalized NDI derivatives for selective detection and facile removal of mercury(ii)

Abstract

Mercury(ii) (Hg2+) has acute toxicity. It is still a challenge to design and synthesize chemosensors for selective detection and removal of Hg2+ in water solutions. By rationally combining the carboxyl group and naphthalene diimide moieties, we obtained a novel water-soluble Hg2+ chemosensor (M2). Interestingly, the sensor M2 showed a dramatic fluorescent “turn-on” response for Hg2+ in water. Moreover, the sensor M2 displayed a high specificity for Hg2+, other cations (including Fe3+, Ag+, Ca2+, Cu2+, Co2+, Ni2+, Cd2+, Pb2+, Zn2+, Cr3+, and Mg2+) had no influence on the Hg2+ detection process. Moreover, the sensor M2 showed high sensitivity for Hg2+, with detection limits of 1.18 × 10−6 M. Even more meaningfully, the sensor M2 can remove Hg2+ from water solutions effectively via the formation of a M2-Hg2+ coordination polymer, which can increase the possibility of M2 being used for practical applications.