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Synthesis of Nanometer-sized Yttrium Oxide Particles in Diisooctyl Sodium Sulphosuccinate/Isooctane Reverse Micelle Solution

dc.contributor.authorCheng, Xuen
dc.contributor.committeechairTissue, Brian M.en
dc.contributor.committeememberDeck, Paul A.en
dc.contributor.committeememberHanson, Brian E.en
dc.contributor.departmentChemistryen
dc.date.accessioned2014-03-14T20:33:06Zen
dc.date.adate1999-04-09en
dc.date.available2014-03-14T20:33:06Zen
dc.date.issued1999-02-24en
dc.date.rdate2000-09-04en
dc.date.sdate1999-04-02en
dc.description.abstractThis thesis describes the synthesis of yttrium oxide nanoparticles in an AOT/isooctane reverse micelle solution. Two synthetic methods are compared. First is the precipitation reaction between yttrium nitrate and ammonia, second is the hydrolysis of yttrium isopropoxide. The effects of annealing of the resulting the yttrium oxide nanoparticles are also described. The nitrate method produced network-like aggregates of yttrium oxide nanoparticles ranging from 10 nm to 40 nm in diameter. Reaction conditions, including the water/AOT ratio (1 to 15), the nitrate concentration (0.02 M to 1.0 M), the ammonia concentration (2 M to 14.8 M), the AOT concentration (0.1 M and 0.5 M), the aging time (1 h to 5 d), and the washing method, were varied to investigate their influence on nanoparticle formation. The optimized synthetic conditions were: a water/AOT ratio of 7.5, [NO₃⁻] = 0.5 M, [NH₃] = 2 M, and [AOT] = 0.1 M. The as-prepared yttrium oxide nanoparticles had highly distorted structures related to the cubic Y2O3 phase. Annealing improved the crystallinity of the as-prepared nanoparticle products and led to larger particles. As annealing temperatures increased, the yttrium oxide nanoparticles gradually evolved into the cubic Y₂O₃ phase. However, an unknown intermediate phase was also observed during the annealing process, which disappeared when the annealing temperature was sufficiently high and the annealing time was long enough (>1000 °C and 4 h). As-prepared products from the isopropoxide hydrolysis also contained network-like nanoparticle aggregates. Particle sizes ranged from 10 nm to 20 nm. Some experimental conditions were varied; they were the water/AOT ratio (10 to 40), the isopropoxide concentration (0.0001 M to 0.003 M), the aqueous phase pH (7.0 and 12.0), the aging temperature (room temperature, approximately 25 °C, and refluxing temperature, approximately, 100 °C), and the aging time (1 h to 5 d). Transmission Electronic Micrographs showed that products of desirable morphology could be produced in a much wider range of experimental conditions by this method compared to those produced by nitrate hydrolysis.en
dc.description.degreeMaster of Scienceen
dc.identifier.otheretd-040299-172943en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-040299-172943/en
dc.identifier.urihttp://hdl.handle.net/10919/31610en
dc.publisherVirginia Techen
dc.relation.haspartxcheng_etd.pdfen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectReverse Micelleen
dc.subjectYttrium Nitrateen
dc.subjectNanoparticleen
dc.subjectAOT/Isooctaneen
dc.subjectYttrium Isopropoxideen
dc.subjectAnnealingen
dc.subjectY2O3en
dc.subjectSynthesisen
dc.titleSynthesis of Nanometer-sized Yttrium Oxide Particles in Diisooctyl Sodium Sulphosuccinate/Isooctane Reverse Micelle Solutionen
dc.typeThesisen
thesis.degree.disciplineChemistryen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

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