Direct Z-Scheme Heterostructures Based on MoSSe Quantum Dots for Visible Light-Driven Photocatalytic Tetracycline Degradation

In this study, Z-scheme MoSSe quantum dots (QDs) are synthesized by a facile hydrothermal process for photodegradation of tetracycline (TC) with visible light activity. Compared to original bulk MoS2 or MoSe2 catalysts, Z-scheme MoSSe QDs display greatly enhanced photodegradation efficiency for TC with the visible light activity. A photodegradation performance of 92.8% for TC has been achieved with visible light irradiation toward 60 min. Also, the optimum TOC removal approached 56.6, 63.8, and 66.7% for TC, RhB, and CR within 60 min, respectively. To the best of our knowledge, the photodegradation rate of 0.1 min–1 for MoSSe QDs is found to be faster (about 5.26–6.25-fold) than those for bulk components. The experimental results certified that superoxide radicals and holes played the major role during the photocatalytic route. This study provides an intense insight into the application of QD photocatalysts and highlights a simple path to create high potential Z-scheme photocatalysts for environmental wastewater pollutant treatment.