Novel visible-light-driven BiFeO<inf>3</inf>-Bi<inf>2</inf>WO<inf>6</inf>nanocomposites toward degradation of dyes

Abstract

© 2017 Elsevier B.V. The different mole ratios of novel visible-light-driven BiFeO3-Bi2WO6nanocomposites were synthesized by a two-step method, i.e. precipitation followed with hydrothermal process. Advanced characterization techniques such as XRD, TEM, UV–vis DRS, BET-specific surface area, PL, and XPS were used to investigate the physical and optical properties of the as-prepared samples. The photocatalytic activities of pure BiFeO3and pure Bi2WO6catalysts for studying the photodegradation of methylene blue (MB) and rhodamine B (RhB) under visible light irradiation were investigated. The results were compared with BiFeO3-Bi2WO6nanocomposites. The highest photocatalytic activity was the 1:1 mol ratio of BiFeO3-Bi2WO6nanocomposite. The increase of photocatalytic activity of BiFeO3-Bi2WO6nanocomposite was ascribed to the charge transfer through the interface of BiFeO3and Bi2WO6catalysts. This effect helps to reduce the recombination of electron-hole pairs. The combination of the synergistic effect of strong visible absorption edge, the amount of BiFeO3and Bi2WO6, and hydroxyl radicals as the active species was established to enhance photocatalytic efficiency. Based on our investigation, the possible photocatalytic mechanism of BiFeO3-Bi2WO6nanocomposite was proposed.