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Preparation and Modification of Carbon Nanotubes and the Prelimilary Application in Glucose Biosensor

Author: LiZuo
Tutor: ZhangXiaoBin
School: Zhejiang University
Course: Materials Physics and Chemistry
Keywords: Carbon nanotubes Catalyst Chemical vapor deposition Modified Glucose sensor
CLC: TP212
Type: PhD thesis
Year: 2005
Downloads: 887
Quote: 1
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Abstract

Carbon nanotubes with diamond same thermal conductivity and unique mechanical properties, a large aspect ratio and nano-scale hollow channels, which scholars have vigorously carry out its field emission electrode modified molecular electronic devices, probes microscope tip, the composite enhancer, gas storage, catalyst support, and many other areas of application. Preparation of carbon nanotube methods are mainly three: the arc discharge method, laser ablation, and chemical vapor deposition method. Relative to the first two methods, chemical vapor deposition rule because of its simple equipment, low reaction temperature, easy to operate, the reaction process easy to control as well as large numbers prepared from the order to the most commonly used method. Despite the current large scale preparation of carbon nanotubes has been great progress, but the catalytic efficiency is still not high, and thus prepared a simple and efficient catalyst to industrial mass production and reduce the cost of production has been a goal of researchers developed. Our aim is to develop a new large scale preparation of carbon nanotubes catalyst exploratory studies on the chemical modification and preliminary application for preparing carbon nanotubes. This article was first prepared using the sol-gel MgMoO ₄ single-phase catalyst. The catalyst can be a larger quantity production of high-quality and high-purity multi-wall carbon nanotubes, after two hours of reaction, the quality of the preparation of carbon nanotubes is nearly 30 times the amount of the original catalyst. In MgMoO ₄ single-phase transition metal doping an appropriate amount of nickel catalyst, the formation of Ni / Mo / MgO catalyst can be more efficiently prepared high-quality high-purity multi-wall carbon nanotubes. Reaction for 2 hours, the maximum yield of carbon nanotubes prepared more than 80 times the original amount of catalyst can be achieved using the catalyst. Moreover, the results of this experiment easily repeated by simply enlarged, per gram of catalyst, a single furnace yield in half an hour can reach more than 40g. MgMoO ₄ studies have shown that single-phase catalyst having good catalytic performance because of the acidic environment suitable for the growth of carbon nanotubes. Before and after reduction MgMoO ₄ catalyst in carbon control 备 process has phase transition occurs. Based on the observation and analysis of experimental data and charts the growth mechanism of multi-walled carbon nanotube bundles catalyst for hydrogen absorption, the reduction of Mo particles precipitates from the catalyst body and form a multilayer Mo nanoparticles dispersed on the support surface leading to the main reason of the carbon nanotubes into a bundle. Catalytic behavior of Ni / Mo / MgO catalyst the reaction atmosphere proportion of catalyst performance, Ni / Mo / MgO catalyst in the growth process of carbon nanotubes phase transition occurs, sufficient carbon source The synergism of both the Ni-Mo improves the carbon atoms in the metal particles into the release rate should be the catalyst has a high efficiency, high-quality carbon nanotubes grown. Prepared for the Preparation of single-walled carbon nanotubes Fe-Mo/MgO catalyst was found to 550 ° C calcined catalyst has the best catalytic performance. The effect of the temperature catalyst activation and more appropriate acidity catalyst has high activity

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