A new zinc-based coordination polymer with blue light emission: synthesis, crystal structure and multifunctional fluorescence sensing properties

Abstract

Coordination compounds offer a special platform for the development of solid state luminescent materials. Herein, a zinc-based coordination polymer with blue light emission, [Zn(cpp)2]n (1), was successfully prepared through the reaction of the Hcpp linker and Zn2+ with d10 configuration under hydrothermal conditions (Hcpp = 1-(4-carboxyphenyl)-3-(pyrazin-2-yl)pyrazole). Compound 1 was characterized by single crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, infrared spectra, and thermogravimetric analysis. Single crystal X-ray diffraction indicates that compound 1 is composed of one four-coordinated Zn2+ and two kinds of cpp− anions with different conformations and displays a one-dimensional chain structure in which 26-membered rings that are perpendicular to each other are linked by shared Zn2+ ions. Luminescence experiments show that compound 1 has apparent blue light emission and can be regarded as a multifunctional luminescent sensor to detect aniline, Fe3+, CrO42− and Cr2O72− through fluorescence quenching. The limit of detections of aniline, Fe3+, CrO42− and Cr2O72− are 2.15 × 10−7 M, 1.09 × 10−7 M, 4.86 × 10−7 M, and 2.57 × 10−7 M, respectively, and the corresponding fluorescence quenching mechanism is investigated in detail.