Visible-light responsive Z-scheme Ti3C2 MXene/In2S3/CeO2 heterojunction for enhanced photocatalytic water purification

Sun-driven photocatalysis has emerged as a promising and sustainable approach for the degradation of organic pollutants in water, offering a green solution to the global challenge of clean water for everybody. The efficiency of this process is largely determined by advanced photocatalysts. Semiconductor-based heterojunctions play a crucial role by facilitating rapid charge transfer, acting as electron mediators for redox reactions, and accelerating photocatalytic activity through synergistic effects. In this study, we successfully fabricated a novel Ti ₃C ₂ MXene/In ₂S ₃/CeO ₂ (TMIC) Z-scheme heterojunction using a simple in situ synthesis and deposition method. Initially, we determined that the optimal ratio of CeO ₂ to In ₂S ₃ was 15 %. After incorporating Ti ₃C ₂ MXene, electro-optical measurements, and catalytic activity tests indicated that the Ti ₃C ₂ MXene _0.0025/In ₂S ₃/CeO ₂ (TM _0.025IC-15 %) heterojunction exhibited the optimal photodegradation performance, degrading over 92 % of methyl orange within 60 min and 99.7 % of diclofenac within 180 min. This performance was superior to both the individual components and other reported heterojunctions. Additionally, the TMIC heterojunction demonstrated excellent stability under our testing conditions and maintained satisfactory activity in a real municipal wastewater treatment plant effluent. This research presents a novel approach to advancing Z-scheme heterojunction photocatalyst design, demonstrating significant potential for practical wastewater treatment.