Large ferroelectric-polarization-modulated photovoltaic effects in bismuth layered multiferroic/semiconductor heterostructure devices. Issue 9 (15th February 2021)

• Record Type: Journal Article
• Authors: Yan, Jian-Min; Wang, Ke; Xu, Zhi-Xue; Ying, Jing-Shi; Chen, Ting-Wei; Yuan, Guo-Liang; Zhang, Tao; Zheng, Hai-Wu; Chai, Yang; Zheng, Ren-Kui
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 9(2021)
• Page Start: 3287
• Page End: 3294
• Publication Date: 2021-02-15
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d0tc05638c
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : Ferroelectrics are appealing candidates for photovoltaic applications. Abstract : Ferroelectrics are appealing candidates for photovoltaic applications. In this study, Bi5 FeTi3 O15 (BFTO) single layer and ZnO/BFTO bilayer films were deposited onto 0.7 wt% Nb-doped SrTiO3 (NSTO) electrically conducting single-crystal substrates to form Ag/BFTO/NSTO and Ag/ZnO/BFTO/NSTO photovoltaic devices. It was found that the insertion of an n-type semiconducting ZnO layer eliminates the built-in electric field between the Ag electrode and the BFTO film and results in the formation of a BFTO/ZnO p–n junction with a built-in electric field whose direction points to the BFTO film. These effects, together with the depolarization field within the BFTO film, provide a favorable energy level alignment for efficient electron extraction. As a result, the short circuit photocurrent density ( J sc ) was improved by nearly 50 fold to 2.2 mA cm −2 and the output power density was increased by 15 fold to 0.09 mW cm −2 under ultraviolet light ( λ = 405 nm) illumination. Upon the reversal of the ferroelectric polarization direction from downward to upward, the J sc and the open circuit voltage ( V oc ) were increased by 2.5 and 4 fold for the Ag/BFTO/NSTO device and by 2.83 and 8.5 fold for the Ag/ZnO/BFTO/NSTO device, respectively. This work provides an effective way for developing efficient ferroelectric and semiconductor based photovoltaic devices.