Two Cu(I\II) Coordination Polymers for Photocatalytic Degradation of Organic Dyes and Efficient Detection of Fe3+ Ions

Abstract

In this work, two new copper-based coordination polymers (CPs), {[CuI(H2PO4)(dpe)]5(dpe)0.5(H2O)7}n (Cu-dpe(I)) and {[CuII(HPO4)(dpe)(H2O)](H2O)3}n (Cu-dpe(II)) (dpe = 1,2-di(4-pyridyl)ethylene), had been successfully constructed by hydrothermal method and solvent evaporation method, respectively, and their crystal structures were determined by single crystal X-ray diffraction. The differences of structure and properties between these two coordination polymers were discussed. The synthetic temperature caused their structure differences. They both exhibit excellent photocatalytic activity toward the degradation of methylene blue (MB) under visible light. The degradation rates of Cu-dpe(I) and Cu-dpe(II) to MB in 120 min under visible light were 88.1% and 97.2%, respectively. Some active free radicals such as ·OH, ·O2−, e− played an important role in degradation of MB. In addition, luminescent experiment revealed Cu-dpe(I) exhibits a relatively high sensitive and selective detection of Fe3+ ions in water solution via fluorescence quenching which was caused by competitive absorption of excitation wavelength energy between Fe3+ and Cu-dpe(I).Graphical Abstract