Preparation, characterization and activity evaluation of p-n junction photocatalyst p-CaFe2O4/n-Ag3VO4 under visible light irradiation

• Published in: Journal of hazardous materials 2009-12, Vol.172 (2-3), p.1415-1423
• Main Authors: Shifu, Chen, Wei, Zhao, Wei, Liu, Huaye, Zhang, Xiaoling, Yu, Yinghao, Chen
• Format: Article
• Language: English
• Subjects: Applied sciences; Catalysis; Catalytic reactions; Chemical engineering; Chemistry; Exact sciences and technology; Ferric Compounds - chemistry; General and physical chemistry; Grinding; Light; Methylene Blue - chemistry; Methylene Blue - radiation effects; Photochemical Processes; Pollution; Reactors; Solid-solid systems; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2009.08.007

p-n junction photocatalyst p-CaFe(2)O(4)/n-Ag(3)VO(4) was prepared by ball milling Ag(3)VO(4) in H(2)O doped with p-type CaFe(2)O(4). The structural and optical properties of the photocatalyst were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and UV-vis diffuse reflection spectrum (DRS). The photocatalytic activity was evaluated by photocatalytic degradation of methylene blue (MB) under visible light irradiation. The results showed that the photocatalytic activity of the p-CaFe(2)O(4)/n-Ag(3)VO(4) was higher than that of Ag(3)VO(4). When the amount of doped p-CaFe(2)O(4) was 2.0 wt.% and the p-CaFe(2)O(4)/n-Ag(3)VO(4) was ball milled for 12h, the photocatalytic degradation efficiency was 85.4%. Effect of ball milling time on the photocatalytic activity of the photocatalyst was also investigated. The mechanisms of the increase in the photocatalytic activity were discussed by the p-n junction principle.