Ferroelectric polarization effect on the photocatalytic activity of Bi0.9Ca0.1FeO3/CdS S-scheme nanocomposites

Yaowen Zhang; Zifei Wang; Jiangwei Zhu; Xuemin He; Hongtao Xue; Sanlong Li; Weiwei Mao; Yong Pu; Xing'ao Li

doi:10.1016/j.jes.2021.09.021

Ferroelectric polarization effect on the photocatalytic activity of Bi_0.9Ca_0.1FeO₃/CdS S-scheme nanocomposites

J Environ Sci (China). 2023 Feb:124:310-318. doi: 10.1016/j.jes.2021.09.021. Epub 2022 Feb 2.

Authors

Yaowen Zhang¹, Zifei Wang², Jiangwei Zhu³, Xuemin He¹, Hongtao Xue¹, Sanlong Li¹, Weiwei Mao⁴, Yong Pu⁵, Xing'ao Li⁶

Affiliations

¹ New Energy Technology Engineering Laboratory of Jiangsu Province & School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
² New Energy Technology Engineering Laboratory of Jiangsu Province & School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China; School of Telecommunications and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
³ Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
⁴ New Energy Technology Engineering Laboratory of Jiangsu Province & School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China; National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China. Electronic address: maoww@njupt.edu.cn.
⁵ New Energy Technology Engineering Laboratory of Jiangsu Province & School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China. Electronic address: puyong@njupt.edu.cn.
⁶ New Energy Technology Engineering Laboratory of Jiangsu Province & School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China; National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China. Electronic address: lxahbmy@126.com.

PMID: 36182141
DOI: 10.1016/j.jes.2021.09.021

Abstract

BiFeO₃ (BFO), as a kind of narrow band-gap semiconductor material, has gradually emerged advantages in the application of photocatalysis. In this paper, Ca doped BFO nanoparticles Bi_0.9Ca_0.1FeO₃ (BCFO) were prepared by sol-gel method. And BCFO and CdS nanocomposites with two morphologies were obtained by controlling the time of loading CdS under a low temperature liquid phase process. It is found that the band gap becomes narrower after doping Ca into BFO, which is conducive to the absorption of visible light. Among all the samples, the composite of CdS nanowires and BCFO nanoparticles obtained by reaction time of 10 min has the best photocatalytic performance. The degradation rate of Methyl Orange solution was 94% after 90 min under visible light irradiation, which was much higher than that of pure BCFO and CdS. Furthermore, significant enhancement in the degradation rate (100% degradation in 60 min) can be achieved in poled samples after electric polarization process. The highest degradation rate is due to the promoted separation of photogenerated carriers induced by the internal polarization field and the formation of S-scheme heterostructure between BCFO and CdS. Such BCFO-CdS nanocomposites may bring new insights into designing highly efficient photocatalyst.

Keywords: BiFeO(3); Nanocomposites; Photocatalytic activity; S-scheme heterojunction.