Preparation and characterization of magnetic core–shell ZnFe2O4@ZnO nanoparticles and their application for the photodegradation of methylene blue

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 217; pp. 185 - 191
• Main Authors: Shao, Rong, Sun, Lin, Tang, Lanqin, Chen, Zhidong
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 01.02.2013; Elsevier
• Subjects: Applied sciences; Catalysis; Catalytic reactions; Chemical engineering; Chemistry; Core–shell structure; Crystallization, leaching, miscellaneous separations; Exact sciences and technology; General and physical chemistry; Photocatalysis; Reactors; Solvothermal method; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; ZnFe2O4@ZnO nanoparticles; ZnFe2O4@ZnO nanoparticles; Core–shell structure; Solvothermal method; Photocatalysis; Scanning electron microscopy; High resolution; @ZnO nanoparticles; Shell structure; Chemical precipitation; Nanoparticle; X ray diffraction; Seeding; Modeling; O; Ultraviolet radiation; Transmission electron microscopy; Preparation; ZnFe; Core-shell structure; Magnetic field; Photochemical degradation
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2012.11.109

► A novel ZnFe2O4@ZnO core–shell photocatalyst was successfully prepared. ► The photocatalyst exhibited higher photocatalytic activity than pure ZnO. ► The composite photocatalyst inhibited the photocorrossion of ZnO to some extent. ► The novel photocatalyst could be easily separated by external magnetic field. Magnetically separable ZnFe2O4@ZnO nanoparticles with enhanced photocatalytic activity were successfully synthesized by two steps. First, ZnFe2O4 nanoparticles (NPs), which served as seeding materials, were synthesized using a solvothermal method. Second, wurtzite ZnO was coated on the ZnFe2O4 particle surfaces on the basis of a chemical precipitation method. The as-prepared samples were characterized with X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), High Resolution Transmission Electron Microscopy (HRTEM) and Energy-dispersive X-ray spectroscopy (EDS). Photodegradation experiments of the samples were carried out by choosing Methylene Blue (MB) as a model target under UV irradiation with homemade photocatalytic apparatus. The results indicated that the obtained core–shell ZnFe2O4@ZnO NPs exhibited higher photocatalytic activity than pure ZnO. In addition, when the molar ratio of ZnFe2O4 to ZnO was 1:10, the obtained product showed the highest photocatalytic activity. Furthermore, the core–shell ZnFe2O4@ZnO NPs could be conveniently separated by using an external magnetic field and the photocorrosion of ZnO was inhibited to some extent.