Chemical Vapor Deposition and Synthesis on Carbon Nanofibers: Sintering of Ferrocene-Derived Supported Iron Nanoparticles and the Catalytic Growth of Secondary Carbon Nanofibers

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• 作者：Wei Xia ; Dangsheng Su ; Alexander Birkner ; Lars Ruppel ; Yuemin Wang ; Christof Wö ; ll ; Jun Qian ; Changhai Liang ; Gabriela Marginean ; Waltraut Brandl ; and Martin Muhler
• 刊名：Chemistry of Materials
• 出版年：2005
• 出版时间：November 15, 2005
• 年：2005
• 卷：17
• 期：23
• 页码：5737 - 5742
• 全文大小：528K
• 年卷期：v.17,no.23(November 15, 2005)
• ISSN：1520-5002

文摘

The synthesis of homogeneously distributed carbon nanofibers with well-defined morphology on vapor-grown carbon nanofibers was achieved by a sequence of gas-phase steps, thus fully avoiding wetchemistry: first, carbon nanofibers were exposed to oxygen plasma to introduce oxygen-containingfunctional groups. Then, the chemical vapor deposition of ferrocene was carried out under oxidizingconditions, yielding nanofiber-supported iron oxide nanoparticles. Secondary carbon nanofibers withdiameters in the range from 10 to 20 nm were subsequently grown from cyclohexane catalyzed by thesintered metallic iron nanoparticles under reducing conditions. XPS was applied to monitor the chemicalchanges of the surface composition and the sintering of the metallic iron particles in hydrogen. Themorphology and the height distribution of the sintered iron oxide nanoparticles was derived by a uniquecombined application of scanning electron microscopy and scanning tunneling microscopy. The specificsurface area of the nanocomposite was enhanced strongly due to the growth of secondary nanofibers,and it was possible to tune the morphology of the nanofiber-nanofiber composites by the processparameters. Thus, a significant advance in the reproducible synthesis of branched carbon fibernanocomposites was achieved.