Z-Scheme heterojunction WO3/ZnIn2S4 solar absorber for wastewater remediation

Abstract

Z-Scheme heterojunction, recognized as one of the optimal methods for the separation of electrons and holes, is extensively applied in the domain of photocatalytic. Leveraging the Z-Scheme heterojunction for photocatalytic and solar interfacial water evaporation presents a promising solution for the purification of dye wastewater and the mitigation of organic pollutant accumulation on traditional solar absorbers. In this study, WO3/ZnIn2S4 heterojunction was synthesized through a two-step solvothermal method, and resulting WO3/ZnIn2S4, which rested on a flexible substrate Ti mesh, possessed the dual functionality of interfacial water evaporation and photocatalytic treatment of dye wastewater, which not only water evaporation rate for WO3/ZnIn2S4 reached 1.26 kgꞏm−2ꞏh−1 but also the Z-Scheme heterojunction WO3/ZnIn2S4 empowered it to effectively degrade dye wastewater, with a degradation rate of Rhodamine B up to 98.6%. The harmonization of these two functionalities effectively circumvented the issue of secondary pollution commonly associated with dye wastewater treatment. This study effectively integrates photocatalysis into a cutting-edge solar-driven interfacial evaporation system, effectively expanding the capabilities of a multifunctional solar absorber and introducing novel applications for zero-discharge dye wastewater treatment.