【作者】 陈长鑫；

【导师】 陈文哲；

【作者基本信息】 福州大学 ， 材料学， 2004， 硕士

【摘要】 为了探索制备碳纳米管的新方法及其制备工艺，本文分别尝试采用了新的脉冲激光轰击原位生长法和CVD基体法两种方法来制备碳纳米管。脉冲激光轰击原位生长法是在常温常压下使用1064nm波长的脉冲激光轰击目标靶与乙醇流动相的固液界面来连续制备含有碳纳米管的溶胶，进而除去乙醇相得到碳纳米管，其中目标靶为石墨与Fe、Ni等金属催化剂混合压制成的靶片；CVD基体法是使用自制的六方介孔MCM-41多孔材料为基体，负载Fe催化剂活性组分，通过CVD法催化裂解C2H2来生长碳纳米管。研究结果表明，该两种方法确实可以生长碳纳米管。结合碳纳米管生长制备试验，分别采用傅立叶红外光谱、紫外－可见光谱、荧光光谱、拉曼光谱、透射电子显微镜、X射线衍射、低温N2吸附等先进的分析测试手段对含碳纳米管溶胶、制备产物和催化剂基体等的形貌、结构、性能进行了表征。激光轰击原位生长法中，通过尝试不同的脉冲激光强度和不同的催化剂来制备碳纳米管，发现激光强度和催化剂对激光法制备碳纳米管有很大的影响作用。当以Ni为催化剂，脉冲激光功率密度为4.5×109W/cm2时制得的碳纳米管质量最好，产物中的无定形碳含量最少，太高或太低的激光功率密度都会降低碳纳米管制备的质量。电镜观察结果表明，使用Fe、Ni作为催化剂制得的碳纳米管管身弯曲，管径为15－45nm左右，管长可达1μm以上。Fe/C、Ni/C目标靶的激光轰击产物都包含有碳纤维和碳纳米颗粒等其它产物。以Ni 为催化剂制备的碳纳米管质量和产量较以Fe为催化剂制备碳纳米管的为高，在其激光轰击产物中还观察到了螺旋状和分枝状等特殊形态的碳纳米管。该方法制得的轰击产物上存在乙醇液相的某些基团，并且产物具有不同于石墨原料的独特的紫外－可见光谱和荧光光谱。CVD基体法制备碳纳米管中，首先探索了不同反应条件对MCM-41材料结构性能和热稳定性的影响，优化工艺参数，结果发现水热条件下反应物的摩尔配比为0.12 C16TMABr：1TEOS：0.24NaOH: 66.7H2O时制得的MCM-41材料最适合用来作为催化剂基体材料，其孔径大小为2.9nm左右。将Fe催化剂活性组分负载于其上具有较高的分散度和催化活性。该方法催化生长的碳纳米管具有管径小且单一，管长较短等特点。更多还原

【Abstract】 Carbon nanotubes were separately synthesized by a new pulsed laser ablation (PLA) for in-situ growth method and CVD support method in this paper. FT-IR, UV-Vis, XFS, LAMAN, TEM, XRD, BET methods were used to characterize the sol, carbon nanotube and other products in the experiment.In the PLA method, the sols containing carbon nanotubes were successively obtained by using 1064nm pulsed laser to ablate the interface of Fe/C, or Ni/C targets and ethanol under common temperature and pressure, and then carbon nanotubes were directly acquired by evaporating the ethanol. The effects of different pulsed laser intensities and catalysts on making carbon nanotubes were systematically investigated. The results show that the better pulsed laser intensity to make the sols is 4.5×109W/cm2. The observation of TEM shows the curve carbon nanotubes with 15-45nm in diameter and above 1μm in length are in-situ synthesized successfully by PLA using Fe or Ni as catalysts. In addition, some ablation products such as carbon fibers and carbon nano-paticals etc. are found. Especially, some special nanotubes states can be also observed as Ni catalyst. The results also show that the output and quality using Ni as catalyst are better than that using Fe catalyst. In CVD support method, carbon nanotubes were prepared with the supported Fe catalyst on the regular mesoporous molecular sieve MCM-41 by catalytic pyrolysis of C2H2. The author studied systematically the effect of different react conditions on the structure, property and thermal-stability of MCM-41, and reached an optimum condition of prepared MCM-41, whose mesoporous diameter was about 2.9nm, with 0.12 C16TMABr: 1TEOS: 0.24NaOH: 66.7H2O under hydro-thermal condition. Carbon nanotubes obtained using this way shows the features of small even diameter and short length.更多还原