Enhanced photocatalytic activity of Fe2O3 decorated Bi2O3

The photo-induced electrons on α-Fe2O3 surface transfer easily to α-Bi2O3 via interfaces; similarly, the photo-induced holes on the α-Bi2O3 surface migrate to α-Fe2O3. Therefore, a larger amount of electrons on the α-Bi2O3 surface and holes on the α-Fe2O3 surface, respectively, resulting in the enhanced separation efficiency of photo-generated charges, which can greatly improve the photocatalytic performance of composites. •Fe2O3 increases the BET surface area of photocatalysts.•Fe2O3 enlarges the light absorption range and decreases the band gap of composites.•The photo-induced charge separation efficiency has been changed.•The photocatalytic activity has been greatly influenced. In this paper, Fe2O3/Bi2O3 composites were fabricated through a pore impregnating method and characterized by BET surface area, X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (DRS) and X-ray photoelectron spectroscopy (XPS). The separation efficiency of photogenerated charges was investigated using benzoquinone (BQ) as scavenger. The composite materials exhibit higher photocatalytic performance toward decolorization of methyl orange (MO) aqueous solution than pure Bi2O3 under both ultraviolet light and simulated solar light irradiation. The relationship between Fe2O3 loading and the photocatalytic performance was discussed and the optimization of the Fe2O3/Bi2O3 composites was obtained. The enhanced mechanism was also discussed.