Z-scheme 3D Bi2WO6/MnO2 heterojunction for increased photoinduced charge separation and enhanced photocatalytic activity

• DOI: 10.1016/j.apsusc.2020.147413
• Publication Date: 2020-08-01T17:22:55Z
• Authors: Hadi Salari; Hadis Yaghmaei
• Keywords: Degradation; Methylene blue; Charge carrier

Abstract In this study, Z-scheme 3D flower like Bi2WO6/MnO2 nanocomposite with excellent photocatalytic performance for organic contaminant degradation in water was successfully synthesized through facile template free method. Physicochemical and structure properties of herterostructure were investigated by XRD, XPS, Raman, BET, SEM, TEM, EDX, DRS, PL, PC and EIS. Results show that the crystallinity is excellent and 3D flower like Bi2WO6 is well connected chemically and electronically with MnO2. The photocatalytic activities were tested for methylene blue degradation under visible light irradiation. The effects of different experiment parameters were investigated on photoactivity of composites. The reaction kinetics is first order and mechanism details were discussed and evaluated by quenching method. The hydroxyl radicals and holes are participated in dye degradation. The synergistic effect induced by formation of 3D Bi2WO6 containing MnO2 nanoparticles drastically improve the charge carrier generation, transfer and separation. The repetitive experiments demonstrate that the Bi2WO6/MnO2 possess good recycle and reusability capacities and after four consecutive cycle, no changes in structure and morphology observed. According to the practical requirement, this structure has the potential to act as an active photocatalyst in water treatment.