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dc.creatorBaker, Chad Allanen_US
dc.date.accessioned2010-06-04T14:48:50Z
dc.date.available2010-06-04T14:48:50Z
dc.date.created2009-08en_US
dc.date.issued2010-06-04T14:48:50Z
dc.date.submittedAugust 2009en_US
dc.identifier.urihttp://hdl.handle.net/2152/ETD-UT-2009-08-363
dc.descriptiontext
dc.description.abstractZnO nanowires were grown using carbothermal reduction and convective vapor phase transport in a tube furnace. Si <100> substrates that were 20 mm x 76.2 mm were sputter coated with 2 nm to 50 nm gold which formed nanoparticles on the order of 50 nm in diameter through a process of Ostwald ripening upon being heated. Growth temperatures were varied from 800ºC to 1000ºC, flow rates were varied from 24 sccm to 3300 sccm, and growth durations were varied from 8 minutes to 5 hours. Vapor phase Zn, CO, and CO2, produced by carbothermal reduction and suspended in an Ar atmosphere, were flowed over the Si substrates. The Au nanoparticles formed an eutectic alloy with Zn, causing them to become liquid nanodroplets which catalyzed vapor-liquid-solid nanowire growth. The nanowires were also synthesized by self-catalyzing vapor-solid growth in some cases. Using the tube furnace never resulted in more than 50% of the substrate being covered by nanowires. It was found that a bench-top furnace could achieve nearly 100% nanowire coverage by placing the 20 mm x 76.2 mm sample face down in a quartz boat less than 2 mm above the source powder. This was because minimizing the distance between the sample and the source powder was critical to achieve macroscopically uniform growth consistently.en_US
dc.format.mimetypeapplication/pdfen_US
dc.language.isoengen_US
dc.subjectnanowiresen_US
dc.subjectnano-wiresen_US
dc.subjectcatalysten_US
dc.subjectcatalyticen_US
dc.subjectvapor-liquid-soliden_US
dc.subjectvapor liquid soliden_US
dc.subjectvapor-soliden_US
dc.subjectvapor soliden_US
dc.subjectvapor-solid-soliden_US
dc.subjectvapor solid soliden_US
dc.subjectcarbothermalen_US
dc.subjectZnOen_US
dc.subjectzinc oxideen_US
dc.subjectnanocombsen_US
dc.subjectnanoen_US
dc.subjectrugosityen_US
dc.subjectvapor transporten_US
dc.subjectvapor phase transporten_US
dc.titleVapor transport techniques for growing macroscopically uniform zinc oxide nanowiresen_US
dc.description.departmentMechanical Engineeringen_US
dc.type.genrethesisen_US
thesis.degree.departmentMechanical Engineeringen_US
thesis.degree.disciplineMechanical Engineeringen_US
thesis.degree.grantorThe University of Texas at Austinen_US
thesis.degree.levelMastersen_US
thesis.degree.nameMaster of Science in Engineeringen_US


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