作者：Ying Huang^a, Changseok Han^a, Yiqing Liu^a, Mallikarjuna N.Nadagouda^b, Libor Machala^c, Kevin E.O’Shea^d, Virender K.Sharma^e, Dionysios D.Dionysiou^a 

^a    Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221, USA

^b    Center for Nanoscale Multifunctional Materials, Mechanical & Material Engineering, Wright State University, Dayton, OH 45431, USA

^c    Regional Centre of Advanced Technologies and Materials, Department of Experimental Physics, Faculty of Science, Palacký University, 771 46 Olomouc, Czech Republic

^d    Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA

^e    Program for the Environmental and Sustainability, Department of Environment and Occupational Health, School of Public Health, Texas A&M University, College Station, TX 77843, USA

摘要：Degradation of atrazine, a widely-used herbicide, by a novel advanced oxidation process was investigated through photo-catalyzing sulfite, the precursor of sulfate radical (SO4−) in this study, by zinc-copper ferrites (ZnxCu1−xFe2O4) under UV–vis light irradiation. The ZnxCu1−xFe2O4 with different ratios of Zn to Cu was synthesized through a facile sol-gel combustion method, and characterized by X-ray powder diffractometry, scanning electron microscopy, transmission electron microscopy, porosimetry, and UV–vis diffuse reflectance spectroscopy, and by a vibrating sample magnetometer and Mössbauer spectrometer. The Zn0.8Cu0.2Fe2O4 demonstrated the highest photocatalytic ability to activate sulfite for the degradation of atrazine under current experimental conditions. The sulfate radical generated in the UV–vis light/Zn0.8Cu0.2Fe2O4/sulfite system was identified as the main reactive species through radical quenching experiments and measuring two important byproducts (atrazine-desethyl and atrazine-desisopropyl). The XPS spectra of fresh and used catalysts were analyzed to further elucidate the reaction mechanisms. There are two possible approaches to produce SO4−: the oxidation of sulfite by photo-generated holes and the accelerated decomposition of metal-sulfito complexes (Fe(III)-sulfito and Cu(II)-sulfito) on the surface of Zn0.8Cu0.2Fe2O4. Based on the detected byproducts, the transformation pathways of atrazine by UV–vis light/Zn0.8Cu0.2Fe2O4/sulfite were proposed as well. After the complete decomposition of atrazine, the used catalysts could be magnetically recovered using a magnet and no sulfite remained in the system. The results suggest that the UV–vis light/Zn0.8Cu0.2Fe2O4/sulfite system is a “green” advanced oxidation technology for future application in wastewater treatment.