Rational design of n-Bi12TiO20@p-BiOI core-shell heterojunction for boosting photocatalytic NO removal

Hongxia Liu; Hui Mei; Shiping Li; Longkai Pan; Zhipeng Jin; Gangqiang Zhu; Laifei Cheng; Litong Zhang

doi:10.1016/j.jcis.2021.08.126

Rational design of n-Bi₁₂TiO₂₀@p-BiOI core-shell heterojunction for boosting photocatalytic NO removal

J Colloid Interface Sci. 2022 Feb;607(Pt 1):242-252. doi: 10.1016/j.jcis.2021.08.126. Epub 2021 Aug 27.

Authors

Hongxia Liu¹, Hui Mei², Shiping Li³, Longkai Pan¹, Zhipeng Jin¹, Gangqiang Zhu⁴, Laifei Cheng¹, Litong Zhang¹

Affiliations

¹ Science and Technology on Thermostructural Composite Materials Laboratory, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, PR China.
² Science and Technology on Thermostructural Composite Materials Laboratory, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, PR China. Electronic address: meihui@nwpu.edu.cn.
³ Department of Physics and Oxide Research Center, Hankuk University of Foreign Studies, Yongin, 17035, Republic of Korea.
⁴ School of Physics and Information Technology, Shaanxi Normal University, Xi' an, 710062, PR China. Electronic address: zgq2006@snnu.edu.cn.

PMID: 34500423
DOI: 10.1016/j.jcis.2021.08.126

Abstract

Bismuth titanate (Bi₁₂TiO₂₀) with unique sillenite structure has been shown to be an excellent photocatalyst for environmental remediation. However, the narrow light-responsive range and rapid recombination of photoinduced electrons-holes limit the photocatalytic performance of Bi₁₂TiO₂₀. To overcome the limitations, a practical and feasibleway is to fabricate heterojunctions by combining Bi₁₂TiO₂₀ with suitable photocatalysts. Here, using a facile chemical precipitation method, a novel and hierarchical core-shell structure of n-Bi₁₂TiO₂₀@p-BiOI (BTO@BiOI) heterojunction was rationally designed and synthesized by loading BiOI nanosheets on BTO nanofibers. The constructed BTO@BiOI composites exhibited significant charge transfer ability due to the synergistic effects of the built-in electric field between BTO and BiOI as well as close interfacial contacts. In addition, the narrow bandgapcharacteristics of the BiOI led to wide light absorption ranges. Therefore, the BTO@BiOI heterojunction exhibited an improved photocatalytic performance under visible light irradiation. The NO removal efficiency of optimal BTO@BiOI was 45.7%, which was significantly higher compared tothat of pure BTO (3.6%) or BiOI (23.1%). Moreover, the cycling experiment revealed that BTO@BiOI composite has a good stability and reusability. The possible mechanism of photocatalytic NO oxidation over BTO@BiOI was investigated in detail.

Keywords: Bi(12)TiO(20)@BiOI; Core-shell; Hierarchical structure; NO removal; p-n heterojunction.