Discrete heterojunction nanofibers of BiFeO3/Bi2WO6: Novel architecture for effective charge separation and enhanced photocatalytic performance

Ran Tao; Xinghua Li; Xiaowei Li; Shuai Liu; Changlu Shao; Yichun Liu

doi:10.1016/j.jcis.2020.03.096

Discrete heterojunction nanofibers of BiFeO₃/Bi₂WO₆: Novel architecture for effective charge separation and enhanced photocatalytic performance

J Colloid Interface Sci. 2020 Jul 15:572:257-268. doi: 10.1016/j.jcis.2020.03.096. Epub 2020 Mar 27.

Authors

Ran Tao¹, Xinghua Li², Xiaowei Li¹, Shuai Liu¹, Changlu Shao³, Yichun Liu¹

Affiliations

¹ Centre for Advanced Optoelectronic Functional Materials Research, and Key Laboratory of UV-Emitting Materials and Technology (Northeast Normal University), Ministry of Education, Changchun 130024, PR China.
² Centre for Advanced Optoelectronic Functional Materials Research, and Key Laboratory of UV-Emitting Materials and Technology (Northeast Normal University), Ministry of Education, Changchun 130024, PR China. Electronic address: lixh781@nenu.edu.cn.
³ Centre for Advanced Optoelectronic Functional Materials Research, and Key Laboratory of UV-Emitting Materials and Technology (Northeast Normal University), Ministry of Education, Changchun 130024, PR China. Electronic address: clshao@nenu.edu.cn.

PMID: 32248077
DOI: 10.1016/j.jcis.2020.03.096

Abstract

Designing and constructing one-dimensional (1D) discrete heterojunctions comprise an ideal strategy to improve the charge-separation efficiency and enhance the photocatalytic activities of semiconductor materials. Here, a novel architecture of discrete heterojunction nanofibers (DH-NFs) was obtained by growing Bi₂WO₆ nanosheets (NSs) on electrospun BiFeO₃ nanofibers (NFs) via solvothermal technology. The charge-separation efficiency of BiFeO₃/Bi₂WO₆ DH-NFs was approximately 2 times higher than that of BiFeO₃ NFs and Bi₂WO₆ NSs. As expected, the BiFeO₃/Bi₂WO₆ DH-NFs exhibited enhanced photocatalytic activities for oxygen evolution and RhB degradation. The reaction rates of BiFeO₃/Bi₂WO₆ DH-NFs for oxygen evolution and RhB degradation were 18.3 and 36.7 times higher, respectively, than those of BiFeO₃ NFs, and 31.9 and 8.7 times higher than those of Bi₂WO₆ NSs, respectively. The improved charge-separation efficiency and enhanced photocatalytic activities of BiFeO₃/Bi₂WO₆ DH-NFs could be attributed to the following three points. The 1D heterojunctions could realize the separation and axial transport of photogenerated charges. The discrete structure could facilitate the spatial separation of redox reaction sites as well as photogenerated charges. The high surface area of BiFeO₃/Bi₂WO₆ DH-NFs might provide more active sites for photocatalytic reaction. Moreover, the BiFeO₃/Bi₂WO₆ DH-NFs possessed good recycling performance owing to the magnetic-separable property derived from the ferromagnetic behavior of BiFeO₃.

Keywords: BiFeO(3)/Bi(2)WO(6) nanofibers; Discrete heterojunctions; Oxygen evolution; Photocatalysis; Pollutant degradation.