【作者】 毕金生；

【导师】 孙保民；

【作者基本信息】 华北电力大学 ， 热能工程， 2012， 硕士

【摘要】 纳米碳管(CNTs)作为一种新型碳材料,具有很好的力学性能、独特的物理化学性质、电学性质和很强的热稳定性,在电子材料、复合材料增强剂、储氢等方面具有潜在的应用价值。合成碳纳米管必需的三要素为：碳源、热源、催化剂,而催化剂具有核心作用,催化剂的种类和性能直接决定了合成碳纳米管的产量和形貌。本文采用V型热解火焰法合成碳纳米管,重点从催化剂角度着手,研究Fe(CO)5和Fe-Mo双金属氧化物做催化剂催化合成碳纳米管的情况。主要考察合成温度、取样方式、取样时间、气体浓度、催化剂制备条件等反应条件对碳纳米管产量和形貌的影响,以获得大量形态单一、直径均匀、管径细小的CNTs为目的,得出最佳的实验工况。结果表明：Fe(CO)5做催化剂,外部基板取样效果理想,碳纳米管的产量和形貌较好,但管径普遍较大。而Fe(CO)5内部取样得到了管径细小的碳纳米管,最细管径达8～10nm,但管的产量较低。Fe(CO)5内部取样的最佳实验工况为：合成温度950℃C,CO流量0.4L/min,取样时间5min。实验证明单金属催化剂中加入第二种组分Mo能够有效提高催化剂活性,Fe-Mo双金属催化剂内部取样得到的碳纳米管产量和形貌都较好,说明此种催化剂比较适合在高温下合成碳纳米管。最佳实验条件为：催化剂煅烧温度600℃,合成温度900℃,取样时间1Omin。通过对取样方式的改进：对催化剂在无碳源的情况下进行预热,实验结果还得到了比较典型的定向碳纳米管阵列。不同催化剂催化合成碳纳米管的最佳生长条件不同,也突出了催化剂的核心作用。更多还原

【Abstract】 Carbon nanotubes (CNTs) as a new type of carbon materials has the very good mechanical properties, the unique physical and chemical, electrical properties and strong thermal stability.It has a potential application value in the electronic materials, composite material strengthening agent, hydrogen storage. Synthetic carbon nanotubes required three elements of:carbon sources, heat source, catalyst. And catalyst has a core function, the category and performance of catalysts directly determine the synthetic production and morphology of carbon nanotubes.In this article, the V-type pyrolysis flame synthesis method of carbon nanotubes, from the perspective of catalyst, the Fe (CO)5and Fe-Mo double metal oxide did catalytic synthesis of carbon nanotubes. We mainly inspected the synthesis temperature, sampling method, sampling time, gas concentration and the catalyst preparation conditions.In order to get a great deal of a single, diameter even, and the form of small diameter CNTs for the purpose, we obtained the best experimental condition.The results showed that:the Fe (CO)5did catalyst, external substrate sampling got ideal effect, carbon nanotubes yield and morphology is better, but generally larger diameter. And Fe (CO)5internal sampling got small diameter of carbon nanotubes, the most fine pipe diameter of8～10nm, but the tube production is low. Fe (CO)5internal sampling best experimental condition was:synthesis temperature950℃, CO flow0.4L/min, sampling time5min. In a single metal catalyst added a second component Mo can effectively improve the catalytic activity. Fe-Mo double metal catalysts internal sampling got the better carbon nanotubes yield and morphology, explained for this catalyst, high temperature was suitable for synthetic carbon nanotubes. Best experimental conditions for:catalyst calcining temperature600℃, the synthesis temperature900℃,sampling time10min. Through the sampling method improvement:no carbon source of catalysts in the preheated, experimental results also had a good directional carbon nanotubes array. In the different catalysts, carbon nanotubes best growth condition is different, this also showed the catalyst is the core of the synthesis of carbon nanotubes.更多还原