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dc.contributor.advisor Liu, Jie en_US
dc.contributor.author Yuan, Dongning en_US
dc.date.accessioned 2009-01-02T16:25:02Z
dc.date.available 2009-01-02T16:25:02Z
dc.date.issued 2008-12-11 en_US
dc.identifier.uri http://hdl.handle.net/10161/931
dc.description Dissertation en_US
dc.description.abstract <p>Controlling the properties of single walled carbon nanotubes (SWNTs) is the major challenge toward their future applications. This dissertation describes several contributions to this chanllenge. </p><p>This dissertation begins with the brief review on carbon nanotubes (CNTs), including discovery, structure, properties, challenges, synthesis and applications. The remaining parts can be divided into three sections. They demonstrate the control of SWNT properties as well as their devices by direct synthesis and metal decoration. </p><p>Two studies are described on the control of SWNT properties by direct synthesis. The first demonstrates the controlled synthesis of SWNTs in terms of their diameter, uniformity, and density by the chemical vapor deposition (CVD) method. The approaches employed include using uniform nanoparticles with specific sizes as catalysts to grow different diameter SWNTs, specially small diameter tubes less than 1 nm; using laser irradiation to grow uniform and high quality SWNTs; and changing the gas flow pattern to obtain different density. The second study demonstrates the growth of aligned SWNTs by flow and substrate guidance. Horizontally aligned ultralong nanotubes are synthesized on Si substrate by both high flow and low flow. The guided growth by the quartz substrate is shown by a large variety of metal catalysts to further the understanding of the growth mechanism. Moreover, top gated FETs have been explored for the selective growth of purely semiconducting, horizontally aligned SWNTs grown on quartz by a ethanol/methanol mixture. </p><p>The control of SWNT device performance is also described, in particular, the correlation between the SWNT field effect transistor (FET) configuration and its gate dependence response. The effects of FET channel length, nanotube density and diameter on the device performance are demonstrated. A model has been constructed in order to simulate the electronic behavior. An interesting metallic behavior has been observed. </p><p>Finally, control of SWNT properties by Palladium decoration after growth is used to manipulate their properties. Moreover, two novel applications including improvement of carbon nanotube film conductivity and catalysis of nanostructure growth are developed.</p> en_US
dc.format.extent 8849910 bytes
dc.format.mimetype application/pdf
dc.language.iso en_US
dc.subject Chemistry, Physical en_US
dc.subject direct synthesis en_US
dc.subject metal decoration en_US
dc.subject diameter en_US
dc.subject allocation en_US
dc.subject chemical vapor deposition en_US
dc.subject field effect transistor en_US
dc.title Property Control of Single Walled Carbon Nanotubes and Their Devices en_US
dc.type Dissertation en_US
dc.department Chemistry en_US

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