Facial Synthesis and Photoreaction Mechanism of BiFeO₃/Bi₂Fe₄O₉ Heterojunction Nanofibers

Abstract

Pure BiFeO3, Bi2Fe4O9, and BiFeO3/Bi2Fe4O9 heterostructure nanofibers were successfully synthesized by a facile wet chemical process followed by an electrospinning technique. Compared with the pure BiFeO3 and Bi2Fe4O9 nanofibers, the introduction of Bi2Fe4O9 in the BiFeO3 makes its absorption edge red shift to absorb much more visible light, and improves its separation efficiency of photogenerated carrier. Besides, the as-obtained BiFeO3/Bi2Fe4O9 nanofibers exhibit higher photocatalytic activity in both the degradation of Rhodamine B and H2 evolution from water under visible-light irradiation. The BiFeO3/Bi2Fe4O9 nanofibers exhibited about 2.7 times and 2.0 times higher H2 evolution than that of pure BiFeO3 and pure Bi2Fe4O9 samples, respectively. The possible photoreactive mechanism of the BiFeO3/Bi2Fe4O9 nanofibers was carefully investigated according to the results of photocatalytic and photoelectric performance, and a Z-scheme mechanism was proposed. Such BiFeO3/Bi2Fe4O9 heterostructure and its composing strategy may bring new insight into the designing of highly efficient visible-light-responsible photocatalysts.

Enhanced Photocatalytic Degradation Activity of BiFeO3 Microspheres by Decoration with g-C3N4 Nanoparticles

“…However, the photocatalytic performance of bare BiFeO 3 is not satisfactory owing to high recombination rate of photogenerated electronhole pairs, and this shortage limits its practical applications in the field of photocatalysis. Therefore, many strategies have been employed to suppress the recombination of photoinduced charges [13][14][15][16][17][18][19] . Among these methods, coupling BiFeO 3 with narrow-bandgap semiconductor of suitable band potential including BiVO 4 , Ag/AgCl, Fe 2 O 3 and Bi 2 Fe 4 O 9 is demonstrated to be an efficient way to promote photogenerated charges migration and separation, and then improve its photocatalytic activity [16][17][18][19] .…”

Complex Catalytic Materials Based on the Perovskite-Type Structure for Energy and Environmental Applications

“…For example, nanofibers of BiFeO 3 /Bi 2 Fe 4 O 9 with enhanced stability show higher efficiency for H 2 production compared to pure BFO and Bi 2 Fe 4 O 9 . This improved efficiency was attributed to the formation of well-defined heterojunctions between the component materials, which helps the separation of charge carriers and avoids their recombination [210]. A significant increase in the photocurrent density compared to pure BFO was also observed for BiFeO 3 /Fe 2 O 3 .…”

In situ Synthesis of Au-Induced Hierarchical Nanofibers/Nanoflakes Structured BiFeO3 Homojunction Photocatalyst With Enhanced Photocatalytic Activity

“…Semiconductor photocatalysis as an efficient and green technology can convert solar energy into chemical energy to dispose of these issues (Wang et al, 2013; Wang H. et al, 2017). In order to fully exploit the solar energy, it is necessary to explore visible light responsive photocatalysts with excellent photocatalytic activities (Zhang et al, 2017).…”

“…Among the variety of visible-light-driven semiconductor materials, BiFeO 3 (BFO) has attracted a great deal of attention due to its narrow band gap (2.2~2.5 eV), good chemical stability and low cost (Wang et al, 2013; Niu et al, 2015). In addition, the room temperature multiferroic property makes it easily recovered from the treated water to avoid the secondary pollution (Zhang et al, 2017). However, the rapid recombination rate of photogenerated electron-hole pairs and low quantum yield limit its practical application (Huo et al, 2011; Srivastav and Gajbhiye, 2012; Niu et al, 2015).…”