A Fe₃O₄-SiO₂-TiO₂ core-shell nanoparticle: Preparation and photocatalytic properties

ABSTRACT

High activity and recycling efficient are exciting characteristics of photocatalysts for water treatment. In this contribution, we report the synthesis methods and photocatalytic properties of Fe₃O₄-SiO₂-TiO₂ core-shell nanoparticles (FST NPs). The magnetic Fe₃O₄, which is synthesized via carbon reduction, is used as core, and the SiO₂ intermitted layer and TiO₂ outside layer are prepared by sol-gel method. The hierarchic structure and the components of the FST NPs were demonstrated by transmission electron microscope and X-ray diffraction. The optimum ratio of alcohol, ester, and water was determined as 4.6:12.3:1 and 30.3:12.5:1 for the SiO₂ and TiO₂ layers, respectively. The X-ray photoelectron spectroscopy, magnetism, and photocatalytic activity of the FST NPs were tested as well. It is found that the methyl orange solution at a concentration of 10 mg/L can be decomposed completely within 240 min by the FST NPs.

KEYWORDS:

• Core-shell structure
• Fe₃O₄-SiO₂-TiO₂ nanoparticles
• magnetic carrier
• sol-gel method

Funding

This research was supported by Shanxi Provincial Natural Science Foundation of China (No. 2012021008-3), and a Project of Shanxi Province Higher Educational Science and Technology Program (No. 20110004).