A zinc2+-dpbt framework: luminescence sensing of Cu2+, Ag+, MnO4− and Cr(vi) (Cr2O72− and CrO42−) ions

Abstract

A unique three-dimensional zinc(II)-dpbt framework with formula {[Zn₆Cl₆(2,2′-dbpt)₃]·4.5H₂O}_n (1) (here, 2,2′-H₂dpbt = 5,5′-di(pyridin-2-yl)-3,3′-bi(1,2,4-triazole)) has been successfully constructed under solvothermal conditions. This complex was fully characterized via single-crystal X-ray diffraction, elemental analysis, powder X-ray diffraction, infrared spectroscopy, thermogravimetric analyses, luminescence spectroscopy, UV-vis spectroscopy, EDS and ICP-MS. The luminescence properties confirm that the emission behavior of the Zn(II) complex exhibits excellent thermal and chemical stabilities. The luminescence performance of 1 in a series of cations and anions was also explored. Importantly, the luminescence experiments reveal that 1 is sensitive, efficient and can be quickly regenerated (at last 4 cycles) as a fluorescent probe for detecting Cu²⁺, Ag⁺, MnO₄⁻ and Cr(VI) (Cr₂O₇²⁻ and CrO₄²⁻) ions.