Synthesis of Magnetic Rattle-Type Nanostructures for Use in Water Treatment
详细信息 查看全文
- 作者：Stuart Linley ; Timothy Leshuk ; Frank X. Gu
- 刊名：ACS Applied Materials & Interfaces
- 出版年：2013
- 出版时间：April 10, 2013
- 年：2013
- 卷：5
- 期：7
- 页码：2540-2548
- 全文大小：389K
- 年卷期：v.5,no.7(April 10, 2013)
- ISSN：1944-8252
文摘
A hydrothermal technique to simultaneously remove a SiO2 template and crystallize a TiO2 outer layer was used to create magnetically separable, hollow rattle-type nanoparticles consisting of a magnetic Fe3O4 core contained within a hollow TiO2 shell. Fe3O4 cores approximately 240 nm in diameter were synthesized, subsequently coated by SiO2 and finally coated with TiO2. This was followed by a hydrothermal treatment to selectively etch the silica, resulting in rattle-type particles with a final outer shell diameter of approximately 390 nm. The product of hydrothermal treatment were rattle-type particles with increased crystallinity and a 68% increase in surface area. Characterization confirmed the ability to etch a hard SiO2 template through use of a simple and benign thermal treatment with pure water, while simultaneously introducing a crystalline phase into the TiO2 active layer. The potential of the particles to be employed as a catalyst in UV induced advanced water treatment for removal of organic contaminants was evaluated through a colorimetric photocatalytic degradation assay using methylene blue as a model contaminant. The ability of the particles to be magnetically separated from solution after treatment and recycled for consecutive treatment cycles was then demonstrated. This technique for selectively removing a hard SiO2 template while simultaneously crystallizing a TiO2 shell avoids the use of hazardous chemical etchants or complex processing, rendering the synthesis of hierarchical, multimaterial, hollow, porous rattle-type particles a simple, attractive, and environmentally friendly 鈥渙ne-pot鈥?technique for potential industrial application.