Greene David, Serrano-Garcia Raquel, Govan Joseph, Gun'ko Yurii K
School of Chemistry and CRANN, Trinity College Dublin, Dublin 2, Ireland.
St. Petersburg National Research University of Information Technologies, Mechanics and Optics, St. Petersburg 197101, Russia.
Nanomaterials (Basel). 2014 Apr 23;4(2):331-343. doi: 10.3390/nano4020331.
In this work, CoFe₂O₄@SiO₂@TiO₂ core-shell magnetic nanostructures have been prepared by coating of cobalt ferrite nanoparticles with the double SiO₂/TiO₂ layer using metallorganic precursors. The Transmission Electron Microscopy (TEM), Energy Dispersive X-Ray Analysis (EDX), Vibrational Sample Magnetometer (VSM) measurements and Raman spectroscopy results confirm the presence both of the silica and very thin TiO₂ layers. The core-shell nanoparticles have been sintered at 600 °C and used as a catalyst in photo-oxidation reactions of methylene blue under UV light. Despite the additional non-magnetic coatings result in a lower value of the magnetic moment, the particles can still easily be retrieved from reaction mixtures by magnetic separation. This retention of magnetism was of particular importance allowing magnetic recovery and re-use of the catalyst.
在本工作中，通过使用金属有机前驱体在钴铁氧体纳米颗粒上包覆双层SiO₂/TiO₂，制备了CoFe₂O₄@SiO₂@TiO₂核壳磁性纳米结构。透射电子显微镜（TEM）、能量色散X射线分析（EDX）、振动样品磁强计（VSM）测量以及拉曼光谱结果证实了二氧化硅层和非常薄的TiO₂层的存在。核壳纳米颗粒在600℃下烧结，并用作紫外光下亚甲基蓝光氧化反应的催化剂。尽管额外的非磁性涂层导致磁矩值较低，但通过磁分离仍可轻松从反应混合物中回收这些颗粒。这种磁性的保留对于实现催化剂的磁回收和再利用尤为重要。
