Magnetically retrievable Fe3O4@SiO2@ZnO piezo-photocatalyst: Synthesis and multiple catalytic properties

Jiang Wu; Kanghui Ke; Ni Qin; Enzhu Lin; Zihan Kang; Dinghua Bao

doi:10.1016/j.jcis.2023.01.009

Magnetically retrievable Fe₃O₄@SiO₂@ZnO piezo-photocatalyst: Synthesis and multiple catalytic properties

J Colloid Interface Sci. 2023 Apr 15:636:167-175. doi: 10.1016/j.jcis.2023.01.009. Epub 2023 Jan 5.

Authors

Jiang Wu¹, Kanghui Ke², Ni Qin², Enzhu Lin², Zihan Kang², Dinghua Bao²

Affiliations

¹ State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China. Electronic address: wujiang6@mail.sysu.edu.cn.
² State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China.

PMID: 36628899
DOI: 10.1016/j.jcis.2023.01.009

Abstract

The piezo-/photocatalytic effects of ZnO have been in the limelight because of their great potential in environmental remediation and energy conversion. However, the poor recyclability of the suspended catalysts can cause inevitable secondary pollution, which is one of the major issues that limit the practical application of these materials. To address this problem, a magnetically retrievable Fe₃O₄@SiO₂@ZnO nanocomposite was designed and successfully synthesized by multi-step reactions. The ZnO nanorods were vertically grown on the surface of the magnetic Fe₃O₄@SiO₂ microspheres, while SiO₂ served as an insulator to protect the inner core and to inhibit charge transfer across the core/shell interface. The Fe₃O₄@SiO₂@ZnO nanocomposite can be easily collected and separated by using a magnetic field. Along with the good recyclability, the material also exhibited high efficiencies in piezocatalytic, photocatalytic and piezo-photocatalytic dye degradation processes. The rate constant of piezo-photocatalysis reached 95.9 × 10^-3 min^-1, which was 2.2 and 6.1 times that of the individual piezocatalysis and photocatalysis, respectively. The present result confirmed the existence of a synergetic effect between piezo- and photocatalytic processes. Hereby, we demonstrated that incorporation of a magnetic carrier is a feasible strategy to achieve retrievable and highly efficient piezo-/photocatalyst.

Keywords: Core-shell; Magnetic retrieve; Photocatalysis; Piezocatalysis; ZnO nanorods.