Synergistic adsorption-photocatalytic activity using Z-scheme based magnetic ZnFe2O4/CuWO4 heterojunction for tetracycline removal

Developing efficient and economical photocatalysts was considered as an efficient and economical strategy for pollution remediation. Herein, magnetically separable ZnFe2O4/CuWO4 composites (ZW) had been developed via combining ZnFe2O4 with CuWO4. The composite with a mass ratio of 40% CuWO4 (ZW-40) performed best, and the tetracycline hydrochloride (TC) removal by adsorption-photocatalysis of ZW-40 reached 86.5%. The photocatalytic degradation rated constant of it was 9.44 x 10(-3) min(-1), which was approximately 5.04 and 3.28 times compared to the ZnFe2O4 and CuWO4 samples, respectively. Pseudo second-order kinetic models could describe well the TC adsorption process, in which chemisorption was the major driving factor, with the maximum adsorption at 23.56 mg g(-1). The improved photo-catalytic capability owed to the formation of Z-scheme heterojunctions with ZnFe2O4 and CuWO4, which improved the intensity of visible light absorption and enhanced the separation electron-hole pairs as well as the redox capability of the composite. ZW-40 was high stability as its removal ability of TC in different water conditions slightly dropped about 15% after 5 cycles. ZW-40 could effectively remove TC in different water matrix, its removal ability for 40 mg/L was as follows: super-pure water > municipal wastewater > swine farm wastewater. Hence, the complexation of ZnFe2O4 with CuWO4 provides a valuable strategy to improve the photocatalytic potential for ZnFe2O4-based catalysts as well as providing a promising pathway for water clarification. (c) 2022 Elsevier B.V. All rights reserved.