Synthesis, Characterization, and Catalytic Applications of Core鈥揝hell Magnetic Carbonaceous Nanocomposites

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• 作者：Changzi Jin ; Yanjie Wang ; Hailian Tang ; Haisheng Wei ; Xin Liu ; Junhu Wang
• 刊名：Journal of Physical Chemistry C
• 出版年：2014
• 出版时间：October 30, 2014
• 年：2014
• 卷：118
• 期：43
• 页码：25110-25117
• 全文大小：485K
• ISSN：1932-7455

文摘

Magnetic resorcinol/formaldehyde resin (RF) and silica/RF nanocomposites with well-defined core鈥搒hell architecture and tunable structural parameters had been prepared via the extended St枚ber method. The carbon counterparts with similar structure and morphology can be obtained by thermal-treating the polymer precursors under N₂ atmosphere. The prepared materials were characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, M枚ssbauer spectroscopy, N₂ physical adsorption/desorption, and thermogravimetric analysis. The catalytic applications of the synthesized magnetic nanocomposites were also explored. It has been shown that the magnetite core was oxidized to 纬-Fe₂O₃ during polymer coating process and further reduced to original Fe₃O₄ phase during carbonization. In addition, the iron oxide core can react with the shell when carbonization temperature reaches 700 掳C. The structural stability of magnetic silica/RF is superior to magnetic RF because of the existence of an inner silica shell. Through a simple deposition鈥損recipitate method, active platinum nanoparticles can be loaded in high dispersity onto the surface of the nanocomposites. The constructed magnetic catalysts are very active in hydrogenation of nitroarenes to corresponding amines and can be separated facilely with an external magnetic field.