Gold Nanoparticles on Mesoporous SiO2-Coated Magnetic Fe3O4 Spheres: A Magnetically Separatable Catalyst with Good Thermal Stability

Molecules

Huan Liu⁴  Chao Lin³  Zhen Ma²  Hongbo Yu¹ 

[1] Ningbo Institute of Materials Engineering and Technology, Chinese Academy of Sciences, Ningbo 315201, China;Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP³), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China;Department of Physics, Faculty of Science, Ningbo University, Ningbo 315211, China;Research Institute of Applied Catalysis, Shanghai Institute of Technology, Shanghai 201418, China

关键词: solvothermal method;    magnetic Fe₃O₄ spheres;    p-nitrophenol;    gold catalysis;   

DOI  :  10.3390/molecules181114258

来源: mdpi

【 摘 要 】

Fe₃O₄ spheres with an average size of 273 nm were prepared in the presence of CTAB by a solvothermal method. The spheres were modified by a thin layer of SiO₂, and then coated by mesoporous SiO₂ (m-SiO₂) films, by using TEOS as a precursor and CTAB as a soft template. The resulting m-SiO₂/Fe₃O₄ spheres, with an average particle size of 320 nm, a high surface area (656 m²/g), and ordered nanopores (average pore size 2.5 nm), were loaded with gold nanoparticles (average size 3.3 nm). The presence of m-SiO₂ coating could stabilize gold nanoparticles against sintering at 500 °C. The material showed better performance than a conventional Au/SiO₂ catalyst in catalytic reduction of p-nitrophenol with NaBH₄. It can be separated from the reaction mixture by a magnet and be recycled without obvious loss of catalytic activity. Relevant characterization by XRD, TEM, N₂ adsorption-desorption, and magnetic measurements were conducted.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.