Enhanced photocatalytic activity of Bi₂WO₆ with oxygen vacancies by zirconium doping

• Published in: Journal of hazardous materials Vol. 196; pp. 255 - 262
• Main Authors: Zhang, Zhijie, Wang, Wenzhong, Gao, Erping, Shang, Meng, Xu, Jiehui
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 30.11.2011; Elsevier
• Subjects: Adsorption; Applied sciences; Bismuth - chemistry; Catalysis; Catalytic reactions; Charge; Chemical engineering; Chemistry; Doping; Electron Transport; electrons; Exact sciences and technology; General and physical chemistry; hypoxia; Light; Microscopy, Electron, Transmission; oxidation; oxygen; Oxygen - chemistry; phenol; Phenol - isolation & purification; Photocatalysis; photocatalyst; Photocatalysts; Photochemical Processes; Photoelectron Spectroscopy; photolysis; Pollution; Reactors; Rhodamines - isolation & purification; Semiconductors; Solutions; superoxide anion; Surface chemistry; Surface Properties; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Time Factors; Tungsten Compounds - chemistry; Vacancies; X-Ray Diffraction; Zirconium; Zirconium - chemistry; Pollutant behavior; Photocatalysis; doped Bi; Doping; RhB; Design; Persistence; Lifetime; Phenol; Adsorption; Visible radiation; Phenols; Zr; WO; Oxidation; Catalyst; Photochemical degradation; Oxygen vacancy
• ISSN: 0304-3894; 1873-3336; 1873-3336
• DOI: 10.1016/j.jhazmat.2011.09.017

To overcome the drawback of low photocatalytic efficiency brought by electron–hole recombination, Bi₂WO₆ photocatalysts with oxygen vacancies were synthesized by zirconium doping. The oxygen vacancies as the positive charge centers can trap the electron easily, thus inhibiting the recombination of charge carriers and prolonging the lifetime of electron. Moreover, the formation of oxygen vacancies favors the adsorption of O₂ on the semiconductor surface, thus facilitating the reduction of O₂ by the trapped electrons to generate superoxide radicals, which play a key role in the oxidation of organics. Visible-light-induced photodegradation of rhodamine B (RhB) and phenol were carried out to evaluate the photoactivity of the products. The results showed that oxygen-deficient Bi₂WO₆ exhibited much enhanced photoactivity than the Bi₂WO₆ photocatalyst free of oxygen deficiency. This work provided a new concept for rational design and development of high-performance photocatalysts.