In-depth insight into the photocatalytic and electrocatalytic mechanisms of Mg3V2O8@Zn3V2O8@ZnO ternary heterostructure toward linezolid: Experimental and DFT studies

Heterogeneous catalysis has been extensively studied as a potential means of overcoming the challenges associated with the detection and elimination of pharmaceutical pollutants in wastewater. In the present study, a novel ternary Mg3V2O8@Zn3V2O8@ZnO (MVO@ZVO@ZnO) composite catalyst was synthesized in three steps using a hydrothermal approach for the first time. The catalytic performance of the composite was investigated for the photodegradation of linezolid (LIZ) under visible light. The LIZ degradation rate of MVO@ZVO@ZnO (the photocatalyst with the optimal composition) was -12, 6.5, 7.8, and 2.6 times higher than those of ZnO, ZVO, MVO, and ZVO@ZnO, respectively. This significantly higher photocatalytic efficiency was attributed to synergism between its constituents, a narrow bandgap, improved light-harvesting ability, and greater charge-carriers separation and migration. Reactive-radical trappi ng experiments demonstrated that hydroxyl and superoxide radicals were largely responsible for LIZ degradation. Assisted by the ultraviolet photoelectron spectroscopy analyses and density functional theory calculations, the charge-carriers pathway and corresponding photocatalytic mechanism were thoroughly discussed in double S-scheme system. Furthermore, the MVO@ZVO@ZnO composite was used as an electrocatalyst to detect small amounts of LIZ in an aqueous medium and exhibited a detection limit of -0.33 & mu;M. We believe that our findings encourage efforts to develop vanadate-based photocatalysts for use in environmental decontamination and detection applications.

Automated summary

In this study, a novel ternary Mg3V2O8@Zn3V2O8@ZnO (MVO@ZVO@ZnO) composite catalyst was synthesized for the photodegradation of Linezolid (LIZ) under visible light. The composite exhibited significantly higher photocatalytic efficiency compared to other catalysts due to synergism between its constituents, narrow bandgap, improved light-harvesting ability, and greater charge-carriers separation and migration. Moreover, the MVO@ZVO@ZnO composite was used as an electrocatalyst to detect small amounts of LIZ in water with a detection limit of -0.33 μM. These findings encourage the development of vanadate-based photocatalysts for environmental decontamination and detection applications.