Jerry Clark (Committee Member), Jason Deibel (Committee Member), Andrew Hsu (Other), Gregory Kozlowski (Advisor), Lok Lew Yan Voon (Other), Benji Maruyama (Committee Member)
Master of Science (MS)
The resistance of three types of bulk carbon nanotube (CNT) materials (floating catalyst CNT yarn, forest grown CNT yarn, and super acid spun CNT fiber) was measured from room temperature to 900 C. Fitting the curves to established conduction equations for disordered materials, competing conduction mechanisms pertaining to the material could be determined. Floating catalyst CNT yarn displayed both semiconductive and metallic isotropic behavior with a resistance minimum, similar to the behavior of crystalline graphite. It was found that, at room temperature, the semiconducting contribution-most likely junctions between CNTs-accounted for 99.99% of the overall resistance. The resistance of forest grown CNT yarn and super acid solution spun CNT fiber decreased monotonically with temperature at a rate similar to amorphous carbon. The impedance of all three materials was also measured to 30 MHz. All three materials followed a series resistor inductor circuit, without any resistance decrease as others have found. Finally, the conductivity and specific conductivity of all three materials was compared to metallic benchmarks. While all three materials had a similar conductivity, the floating catalyst CNT yarn had a significantly higher specific conductivity.
Department or Program
Department of Physics
Year Degree Awarded
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