Efficient removal of lomefloxacin by Z-scheme MrGO/Ag2WO4 heterojunction recyclable composite under visible light: Mechanism of adsorption and photodegradation

In this study, we have developed a magnetic MrGO/Ag 2 WO 4 composite to remove lomefloxacin (LOM) via the synergistic effect of adsorption and photocatalysis in water. After 20 min of dark reaction and 120 min of visible light reaction, the MrGO/Ag 2 WO 4 composite can remove 93.62% of LOM, and the removal effect is still 85.49% after four cycles, the maximum adsorption capacity is 117.93 mg/g. Compared with MrGO and MrGO/Ag 2 WO 4 separately, the ability of MrGO/Ag 2 WO 4 composite to remove LOM increased by 2.15 and 7.25 times. The e − , h + , •OH, and •O 2 − all play an essential role during degradation. Moreover, the high activity of MrGO/Ag 2 WO 4 composite material is attributed to the excellent adsorption performance and the formation of Z-scheme heterojunction , which effectively aggregates organic matter and inhibits the recombination of photogenerated carriers. Finally, the adsorption and photocatalytic mechanism of MrGO/Ag 2 WO 4 composite materials for LOM are discussed, the adsorption process of the LOM by MrGO/Ag 2 WO 4 composite is more suitable for the Langmuir isotherm adsorption model and may be more inclined to a monolayer system. The results suggest that MrGO/Ag 2 WO 4 holds a high potential of being an environmentally friendly and recyclable composite catalyst for LOM removal from water.