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dc.contributor.advisorHall, Matthew Johnen
dc.creatorBaker, Chad Allanen
dc.date.accessioned2010-06-04T14:48:50Zen
dc.date.available2010-06-04T14:48:50Zen
dc.date.created2009-08en
dc.date.issued2010-06-04T14:48:50Zen
dc.date.submittedAugust 2009en
dc.identifier.urihttp://hdl.handle.net/2152/ETD-UT-2009-08-363en
dc.descriptiontexten
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
dc.format.mimetypeapplication/pdfen
dc.language.isoengen
dc.subjectnanowiresen
dc.subjectnano-wiresen
dc.subjectcatalysten
dc.subjectcatalyticen
dc.subjectvapor-liquid-soliden
dc.subjectvapor liquid soliden
dc.subjectvapor-soliden
dc.subjectvapor soliden
dc.subjectvapor-solid-soliden
dc.subjectvapor solid soliden
dc.subjectcarbothermalen
dc.subjectZnOen
dc.subjectzinc oxideen
dc.subjectnanocombsen
dc.subjectnanoen
dc.subjectrugosityen
dc.subjectvapor transporten
dc.subjectvapor phase transporten
dc.titleVapor transport techniques for growing macroscopically uniform zinc oxide nanowiresen
dc.contributor.committeeMemberShi, Li, Ph. D.en
dc.description.departmentMechanical Engineeringen
dc.type.genrethesisen
thesis.degree.departmentMechanical Engineeringen
thesis.degree.disciplineMechanical Engineeringen
thesis.degree.grantorThe University of Texas at Austinen
thesis.degree.levelMastersen
thesis.degree.nameMaster of Science in Engineeringen


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