Facile synthesis of Cu-complex for visible-light photodegradation of organic dyes and sulfonamide antibiotics with added H2O2

Abstract

In this article, copper complex [Cu(biba) 2 ]·H 2 O (biba = 2-(1H-benzoimidazol-2-yl)benzoic acid) was synthesized via hydrothermal method, and structurally characterized by single-crystal X-ray diffraction, powder X-ray diffraction, UV-Vis diffuse reflectance spectra, Raman spectra and Fourier-transform infrared spectroscopy. [Cu(biba) 2 ]·H 2 O exhibited good photocatalytic activities in degradation of methylene blue (MB) dye and sulfadiazine (SD) antibiotic under visible light with added H 2 O 2 . The degradation efficiency of MB was up to 93.1% after reacting for 80 min, and the degradation efficiency of SD was over 96.8% after reacting for 60 min. The degradation kinetics of MB and SD under [Cu(biba) 2 ]·H 2 O/H 2 O 2 catalytic system was studied, and the observed first-order kinetics rate constants ( k ) were 0.0340 and 0.0573 min –1 , respectively. Based on the experimental results, a reasonable mechanism was proposed to interpret the photo-Fenton oxidation process.