Two Bisligand-Coordinated Luminescent Zn(Ⅱ)-Coordination Polymers for Sensing of Ions and Pesticides in Aqueous Solutions

Two coordination polymers(CPs) [Zn(PTA)(DTP)(H2O)2]·(DMF)(CP-1) and [Zn(BTC)(DTP)]·(CH3CN)1.5·(H2O)4(CP-2) with one-and two-dimensional architectures were synthesized from Zn(Ⅱ) ion and different organic linkers like terephthalic acid(H2PTA), benzene-1,3,5-tricarboxylic acid(H3BTC), and 3,5-di(1,2,4-triazol-1-yl) pyridine(DTP). The fluorescent sensing experiments showed that the two CPs displayed effective, sensitive, and selective abilities towards Fe3+and Cr2O72-. For sensing the pesticides, CP-1 outperforms in sensing of metamitron(MMT) and CP-2 is ultrasensitive towards imidacloprid(IMI). The possible mechanisms involved in the quenching of the fluorescence intensity include the inner filter effect(IFE) and the fluorescence resonance energy transfer(FRET) effect.