Continuous Deposition of Carbon Nanotubes in an Arc-reactor and their Application in Field Emission Devices

dc.contributor.authorShastry, Rahulen
dc.date.accessioned2009-12-17T02:09:42Z
dc.date.available2009-12-17T02:09:42Z
dc.date.issued2007en
dc.description.abstractCarbon nanotubes have become one of the most important building blocks critical to nanotechnology. Carbon nanotubes have attracted the interests of many scientists since their discovery due to their remarkable properties and have been widely used for various applications. However, the bottle neck in nanotube research has been the lack of a cheap, continuous and fast nanotube production method. This study concerns a reactor where nanotubes are continuously deposited on a carbon substrate using arc discharge at atmospheric pressure. This process appears to be the first to employ an arc discharge as the method for continuous mass deposition of nanotubes on a substrate. This nanotube deposition method eliminates the generic multistep process of nanotube deposition on substrates for its use in many applications. The effect of various parameters influencing growth and morphology of nanotubes on the substrate in the arc reactor (inter-electrode gap, atmosphere composition, current density, flushing, substrate type and speed and catalyst) have been systematically explored to optimise nanotube growth. The field emission properties of the nanotube laden substrate are studied for use and applicability as electron emitters. The nanotube samples demonstrated superior emission properties, low turn-on field and excellent current stability when put into applications such as a luminescent tube and an ionisation sensor. Theoretical modelling of the behaviour of a single nanotube during field emission was performed using finite element analysis software (COMSOL 3.2) to understand the effect of nanotube length, diameter, and vacuum gap on an individual nanotube. The results reveal that resistive heating (temperature) limits the maximum current carried by an individual nanotube. Furthermore, a new growth model is introduced to explain the formation of nanotubes from graphene fragments and nanocrystallites, due to polarisation of carbon species near the electrode surface suggesting that carbon vapour is unlikely to be responsible for nanotube growth.en
dc.identifier.urihttp://hdl.handle.net/10092/3267
dc.identifier.urihttp://dx.doi.org/10.26021/1594
dc.language.isoen
dc.publisherUniversity of Canterbury. Chemical and Process Engineeringen
dc.relation.isreferencedbyNZCUen
dc.rightsCopyright Rahul Shastryen
dc.rights.urihttps://canterbury.libguides.com/rights/thesesen
dc.subjectCarbon nanotubesen
dc.subjectnanotechnologyen
dc.subjectarc dischargeen
dc.subjectcontinuousen
dc.subjectfield emissionen
dc.subjectionisation sensoren
dc.titleContinuous Deposition of Carbon Nanotubes in an Arc-reactor and their Application in Field Emission Devicesen
dc.typeTheses / Dissertations
thesis.degree.disciplineChemical Engineering
thesis.degree.grantorUniversity of Canterburyen
thesis.degree.levelDoctoralen
thesis.degree.nameDoctor of Philosophy
uc.bibnumber1070700
uc.collegeFaculty of Engineeringen
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