Enhanced optical properties and the origin of carrier transport in BiFeO3/TiO2 heterostructures with 109° domain walls

JOURNAL OF ALLOYS AND COMPOUNDS

卷:628

Article

Feng, Hong-Jian¹  Wang, M.¹  Liu, F.²  Duan, B.¹  Tian, J.²  Guo, X.² 

[1] NW Univ Xian, Sch Phys, Xian 710069, Peoples R China

[2] Chinese Acad Sci, Xian Inst Opt & Precis Mech, State Key Lab Transient Opt & Photon, Xian 710119, Peoples R China

关键词: BiFeO3/TiO2 heterostructures;    Optical absorption;    Carrier transport;    First-principles;   

DOI  :  10.1016/j.jallcom.2014.11.211

来源: Elsevier

【 摘 要 】

The absorption coefficient in the BiFeO3/TiO2 bilayer film prepared by simple sol-gel method has been significantly improved relative to BiFeO(3)and TiO2 film. Terahertz-radiation emission presents a direct evidence for the photon-induced carrier transport in the heterostructures. First-principles calculations agree well with the experiments and present an unambiguous explanation for the charge carrier transport and the enhanced absorbance. It is induced by the large electrostatic potential drop in the interface with the 109 degrees domain walls and the reduced recombination of electron-hole pairs in the BiFeO3 side of the heterostructure. This work provides a new route toward designing novel photovoltaic heterostructures with high efficiency. (C) 2014 Elsevier B.V. All rights reserved.

【 授权许可】

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