Synthesis of double-shelled sea urchin-like yolk-shell Fe3O4/TiO2/Au microspheres and their catalytic applications. (10th February 2015)

• Record Type: Journal Article
• Authors: Li, Jie; Tan, Li; Wang, Ge; Yang, Mu
• Is Part Of: Nanotechnology. Volume 26:Number 9(2015)
• Publication Date: 2015-02-10
• Subjects: yolk-shell -- sea urchin-like -- Au nanoparticles -- magnetite -- TiO2 -- catalytic reduction; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/0957-4484/26/9/095601
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: Double-shelled sea urchin-like yolk-shell Fe3 O4 /TiO2 /Au microspheres were successfully synthesized through loading Au nanoparticles on the Fe3 O4 /TiO2 support by a in situ reduction of HAuCl4 with NaBH4 aqueous solution. These microspheres possess tunable cavity size, adjustable shell layers, high structural stability and large specific surface area. The Au nanoparticles of approximately 5 nm in diameter were loaded both on the TiO2 nanofibers and inside the cavities of sea urchin-like yolk-shell Fe3 O4 /TiO2 microspheres. The sea urchin-like structure composed of TiO2 nanofibers ensure the good distribution of the Au nanoparticles, while the novel double-shelled yolk-shell structure guarantees the high stability of the Au nanoparticles. Furthermore, the Fe3 O4 magnetic core facilitates the convenient recovery of the catalyst by applying an external magnetic field. The Fe3 O4 /TiO2 /Au microspheres display excellent activities and recycling properties in the catalytic reduction of 4-nitrophenol (4-NP): the rate constant is 1.84 min −1 and turnover frequency is 5457 h −1 .