Chemical processing and structural simulations of electronic materials in the barium-oxide - titanium-dioxide system.

Persistent Link:
http://hdl.handle.net/10150/184672
Title:
Chemical processing and structural simulations of electronic materials in the barium-oxide - titanium-dioxide system.
Author:
Phule, Pradeep Prabhakar.
Issue Date:
1989
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Novel low temperature wet chemical processes for the synthesis of gels and ultrafine powders of BaTiO₃ and BaTi₄O₉ were developed. Under acidic conditions a titanyl acylate precursor was obtained by molecular modification of titanium isopropoxide. In the sol-gel process, amorphous BaTiO₃ gels obtained under acidic conditions were heat treated at ≈950-1000°C yielding fine (≈ 1-3 μm), high purity (99.9%) stoichiometric (Ba/Ti = 0.99) BaTiO₃ powders. In the sol-precipitation process, ultrafine (≈ 10 nm) crystalline BaTiO₃ powders were directly precipitated at low temperatures (<100°C) from a stoichiometric titanium acylate- barium acetate sol (pH > 13.5). Precursor powders obtained by hydrolytic decomposition of barium and titanium alkoxides were heat treated at 1100°C to obtain high purity, homogeneous, single phase BaTi₄O₉ powders. Atomistic pathways for the evolution of crystalline phases from amorphous gels and powders were investigated. The microstructure and electrical properties of sintered BaO-TiO₂ ceramics were studied and correlated with the powder processing conditions. The structures of crystalline and amorphous forms of some materials in the BaO-TiO₂ system were simulated using molecular dynamics computer techniques to develop a fundamental understanding of structure-property relationships for BaTiO₃ and TiO₂ containing glasses.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Barium compounds.; Titanium compounds.; Electronic ceramics.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Materials Science and Engineering; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Risbud, S. H.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleChemical processing and structural simulations of electronic materials in the barium-oxide - titanium-dioxide system.en_US
dc.creatorPhule, Pradeep Prabhakar.en_US
dc.contributor.authorPhule, Pradeep Prabhakar.en_US
dc.date.issued1989en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractNovel low temperature wet chemical processes for the synthesis of gels and ultrafine powders of BaTiO₃ and BaTi₄O₉ were developed. Under acidic conditions a titanyl acylate precursor was obtained by molecular modification of titanium isopropoxide. In the sol-gel process, amorphous BaTiO₃ gels obtained under acidic conditions were heat treated at ≈950-1000°C yielding fine (≈ 1-3 μm), high purity (99.9%) stoichiometric (Ba/Ti = 0.99) BaTiO₃ powders. In the sol-precipitation process, ultrafine (≈ 10 nm) crystalline BaTiO₃ powders were directly precipitated at low temperatures (<100°C) from a stoichiometric titanium acylate- barium acetate sol (pH > 13.5). Precursor powders obtained by hydrolytic decomposition of barium and titanium alkoxides were heat treated at 1100°C to obtain high purity, homogeneous, single phase BaTi₄O₉ powders. Atomistic pathways for the evolution of crystalline phases from amorphous gels and powders were investigated. The microstructure and electrical properties of sintered BaO-TiO₂ ceramics were studied and correlated with the powder processing conditions. The structures of crystalline and amorphous forms of some materials in the BaO-TiO₂ system were simulated using molecular dynamics computer techniques to develop a fundamental understanding of structure-property relationships for BaTiO₃ and TiO₂ containing glasses.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectBarium compounds.en_US
dc.subjectTitanium compounds.en_US
dc.subjectElectronic ceramics.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineMaterials Science and Engineeringen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorRisbud, S. H.en_US
dc.contributor.committeememberRaghavan, S.en_US
dc.contributor.committeememberDeymier, P. A.en_US
dc.contributor.committeememberPemberton, J. E.en_US
dc.contributor.committeememberBurke, M. F.en_US
dc.identifier.proquest8915980en_US
dc.identifier.oclc702370960en_US
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