Electrospun Cr-doped Bi4Ti3O12/Bi2Ti2O7 heterostructure fibers with enhanced visible-light photocatalytic properties

Abstract

A series of Cr-doped Bi₄Ti₃O₁₂/Bi₂Ti₂O₇ (BTO) heterostructure fibers have been synthesized via a one-step, facile and economical electrospinning/calcination process. SEM and TEM results reveal that the diameters of the as-prepared fibers are 100 ± 30 nm. The light adsorption of Bi₄Ti₃O₁₂ and Bi₂Ti₂O₇ in the fibers has been remarkably improved by Cr doping. With increased Cr doping, XRD and XPS show that the amount of Bi₂Ti₂O₇ increases in the fibers. As a result, the Bi₄Ti₃O₁₂/Bi₂Ti₂O₇ heterojunction structure is enhanced, which further promotes the charge separation of photogenerated charge carriers. Photocatalytic tests indicated that the as-prepared Cr-doped Bi₄Ti₃O₁₂/Bi₂Ti₂O₇ fibers exhibit good photocatalytic activity for photodegradation of methyl orange (MO) under visible-light irradiation.