Synthesis Of Carbon Nanotubes From Liquid -hydrocarbon Diffusion Flame

Since carbon nanotubes were discovered and designated in 1991, the particular capabilities of this new carbon material absorbed extensive interest of many areas such as physics, chemistry and materials science. A lot of scientists studied and produced many synthesis methods of carbon nanotubes. On the basis of summarizing others' studies, a novel method for synthesizing multi-walled carbon nanotubes is proposed by using liquid-hydrocarbon flame on austenitic stainless steel substrates, and without directly seeding catalyst into the flame. Well-aligned carbon nanotubes can be produced by using appropriate processing technics. While using normal carbon steel as substrate, carbon nanofibers can be synthesized. This paper discusses the processing parameters while synthesizing carbon nanotubes and nanofibers from liquid-hydrocarbon diffusion flame in detail and the relationship between them and the micro-appearances. By contrast with those conventional synthesis methods, with many merits and high capabilities for large scale operation, flames synthesis offers promise for bulk synthesis of carbon nanotubes and nanofibers for a variety of applications.The content of this paper contains:Chapter one introduces the basic concepts, developing course, research significance, application foreground and the present research state of other countries in the world.Chapter two introduces the structure characteristic and the performances and applications in the areas such as mechanics, physics and chemistry, then analyzes the present state, existing problem and developing trend of nanotubes research.Chapter three introduced several synthesis methods and purification methods of nanotubes and nanofibers detailedly.Chapter four concentrates on the research of two foreign research groups who use carbon-hydrogen gases flames to produce carbon nanotubes.Chapter five introduces the detail technics process of synthesis of carbon nanotubes by using liquid-hydrocarbon diffusion flame.Chapter six discussesand analyzes the effects of every technics paramenters on the nanotubes produced by using liquid-hydrocarbon diffusion flame.Chapter seven analyzes the SEM and TEM micro-appearances of the nanotubes produced by liquid-hydrocarbon diffusion flame and draws the conclusion of the nanotubes' cluster growth mechanism.Chapter eight analyzes the SEM and TEM micro-appearances of the nanofibes produced by liquid-hydrocarbon diffusion flame, and considers that the growth mechanism of nanotubes and nanofibers is different.Chapter nine summarizes the whole thesis and probes into the developing direction of this research, which is concerned to be helpful for the continued research.