Design Principles of Carbon Nanostructures as Highly Efficient Metal-free Catalysts
文献类型：会议论文
| 作者 | Zhang J(张建) ; Jian Zhang*1 and Dangsheng Su2 |
| 出版日期 | 2012-10-21 |
| 会议名称 | 1st International Conference on Emerging Advanced Nanomaterials (ICEAN) |
| 会议日期 | 2012-10-21 |
| 会议地点 | 澳大利亚布里斯班 |
| 页码 | 1—1 |
| 通讯作者 | 张建 |
| 中文摘要 | Carbon nanomaterials including nanotubes, nanographite and nanodiamond, have been proved to efficiently catalyze the conversion of alkanes to alkenes [1-5]. The chemical-vapor-deposition (CVD) process is sufficiently well developed to allow the large-scale production of carbon nanotubes (CNTs). Metal nanoparticles (Fe, Co, Ni, etc.) are usually immobilized on a solid support and then decompose the gaseous hydrocarbon feedstocks into fragmented carbon units at elevated temperatures of 700-1100°C. Metal carbides are formed and then these dominate the growth of filamentous carbon as a structural template. The produced CNTs cannot stay firmly with an inert support and so inevitably detach away, especially during liquid-phase purification or mechanical treatment. The biggest difficulties when handling the loose powder are filtration in the slurry-phase operations and the large pressure drops in fixed-bed reactors. These problems very much limit the application of CNTs on a large scale. The fabrication of carbon filaments on a structured support (e.g., activated carbon, carbon fibers, porous frameworks, graphite) has also suffered from discontinuities in the structure. The future use of CNTs has also been restricted by the technical requirements and the necessary high energy consumption to operate the intense and complicated CVD process. To avoid any mechanical post-treatment of powder and the risk of explosion during CVD synthesis, we have explored a simple method to produce monolithic CNTs directly as millimeter-scale spheres, featuring an integral continuity in the structure from microscopic to macroscopic scales [6]. The whole process of CNTs growth has been conducted in a flow of ultrapure N, involving a set of elementary steps in the solid phase being less complex than the widely used CVD process. The growth of CNTs is based on a solid reaction mechanism and well-graphitized nanotubes can be obtained even at a temperature as low as 400°C. Direct observation of all growth events is made by using in-situ transmission electron microscopy (TEM), X-ray diffraction (XRD), IR, Raman spectroscopy and thermogravimetric analysis. |
| 会议录 | 1st International Conference on Emerging Advanced Nanomaterials (ICEAN)会议论文集
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| 会议录出版地 | 澳大利亚布里斯班 |
| 源URL | [http://ir.nimte.ac.cn/handle/174433/10181]  |
| 专题 | 宁波材料技术与工程研究所_宁波所知识产出 |
| 推荐引用方式 GB/T 7714 | Zhang J,Jian Zhang*1 and Dangsheng Su2. Design Principles of Carbon Nanostructures as Highly Efficient Metal-free Catalysts[C]. 见:1st International Conference on Emerging Advanced Nanomaterials (ICEAN). 澳大利亚布里斯班. 2012-10-21. |
入库方式： OAI收割
来源：宁波材料技术与工程研究所
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