Microstructural and Nonohmic Properties of ZnO center dot Pr6O11 CoO Polycrystalline System

Detalhes bibliográficos
Autor(a) principal: Ramírez, Miguel Angel [UNESP]
Data de Publicação: 2010
Outros Autores: Fernández, José Francisco, Frutos, José de, Longo, Elson [UNESP], Varela, José Arana [UNESP]
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Institucional da UNESP
Texto Completo: http://dx.doi.org/10.1590/S1516-14392010000100008
http://hdl.handle.net/11449/131704
Resumo: The microstructure and electrical properties of varistors composed of (95-x) ZnO + x Pr6O11+ 5 CoO (ZPC), (x = 0.1, 0.5 and 1.0) and sintered at 1300 and 1350 degrees C, were investigated. According to X-ray diffraction, several phases (ZnO, Pr2O3 and Pr2CoO4) are present when x = 1.0. Using Scanning Electron Microscopy, all of these compositions contain precipitates. These phases are important regarding the development of the microstructure and the electrical properties. The samples with x = 0.1 introduce the best nonohmic behavior (alpha = 9.0), however when x = 0.5 the electrical properties are highly degraded due to the small quantity of effective barriers. The density of superficial states N-IS and donor concentration Nd decreases with Pr6O11 addition. The decrease in the donor concentration is attributed to the annihilation of the donor defects according to the transformation of praseodymium oxides from Pr6O11 to Pr2O3.
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spelling Microstructural and Nonohmic Properties of ZnO center dot Pr6O11 CoO Polycrystalline Systemelectrical propertiesvaristorsgrain boundarymicrostructureThe microstructure and electrical properties of varistors composed of (95-x) ZnO + x Pr6O11+ 5 CoO (ZPC), (x = 0.1, 0.5 and 1.0) and sintered at 1300 and 1350 degrees C, were investigated. According to X-ray diffraction, several phases (ZnO, Pr2O3 and Pr2CoO4) are present when x = 1.0. Using Scanning Electron Microscopy, all of these compositions contain precipitates. These phases are important regarding the development of the microstructure and the electrical properties. The samples with x = 0.1 introduce the best nonohmic behavior (alpha = 9.0), however when x = 0.5 the electrical properties are highly degraded due to the small quantity of effective barriers. The density of superficial states N-IS and donor concentration Nd decreases with Pr6O11 addition. The decrease in the donor concentration is attributed to the annihilation of the donor defects according to the transformation of praseodymium oxides from Pr6O11 to Pr2O3.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CYTEDUniversidade Estadual Paulista Instituto de QuímicaInstituto de Cerámica y Vidrio Departamento de ElectrocerámicaUniversidad Politécnica de Madrid ETSITUniv Estadual Paulista, Inst Quim, BR-14801970 Araraquara, SP, BrazilUniversidade Federal de São Carlos (UFSCar), Dept Engenharia MaterialsUniversidade Estadual Paulista (Unesp)Inst Ceram & VidrioUniv Politecn MadridRamírez, Miguel Angel [UNESP]Fernández, José FranciscoFrutos, José deLongo, Elson [UNESP]Varela, José Arana [UNESP]2014-05-20T14:18:19Z2014-05-20T14:18:19Z2010-01-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article29-34application/pdfhttp://dx.doi.org/10.1590/S1516-14392010000100008Materials Research-ibero-american Journal of Materials. São Carlos: Universidade Federal de São Carlos (UFSCar), Dept Engenharia Materials, v. 13, n. 1, p. 29-34, 2010.1516-1439http://hdl.handle.net/11449/13170410.1590/S1516-14392010000100008S1516-14392010000100008WOS:000276894200008S1516-14392010000100008.pdfWeb of Sciencereponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengMaterials Research-ibero-american Journal of Materials1.1030,398info:eu-repo/semantics/openAccess2023-11-24T06:16:20Zoai:repositorio.unesp.br:11449/131704Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462023-11-24T06:16:20Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false
dc.title.none.fl_str_mv Microstructural and Nonohmic Properties of ZnO center dot Pr6O11 CoO Polycrystalline System
title Microstructural and Nonohmic Properties of ZnO center dot Pr6O11 CoO Polycrystalline System
spellingShingle Microstructural and Nonohmic Properties of ZnO center dot Pr6O11 CoO Polycrystalline System
Ramírez, Miguel Angel [UNESP]
electrical properties
varistors
grain boundary
microstructure
title_short Microstructural and Nonohmic Properties of ZnO center dot Pr6O11 CoO Polycrystalline System
title_full Microstructural and Nonohmic Properties of ZnO center dot Pr6O11 CoO Polycrystalline System
title_fullStr Microstructural and Nonohmic Properties of ZnO center dot Pr6O11 CoO Polycrystalline System
title_full_unstemmed Microstructural and Nonohmic Properties of ZnO center dot Pr6O11 CoO Polycrystalline System
title_sort Microstructural and Nonohmic Properties of ZnO center dot Pr6O11 CoO Polycrystalline System
author Ramírez, Miguel Angel [UNESP]
author_facet Ramírez, Miguel Angel [UNESP]
Fernández, José Francisco
Frutos, José de
Longo, Elson [UNESP]
Varela, José Arana [UNESP]
author_role author
author2 Fernández, José Francisco
Frutos, José de
Longo, Elson [UNESP]
Varela, José Arana [UNESP]
author2_role author
author
author
author
dc.contributor.none.fl_str_mv Universidade Estadual Paulista (Unesp)
Inst Ceram & Vidrio
Univ Politecn Madrid
dc.contributor.author.fl_str_mv Ramírez, Miguel Angel [UNESP]
Fernández, José Francisco
Frutos, José de
Longo, Elson [UNESP]
Varela, José Arana [UNESP]
dc.subject.por.fl_str_mv electrical properties
varistors
grain boundary
microstructure
topic electrical properties
varistors
grain boundary
microstructure
description The microstructure and electrical properties of varistors composed of (95-x) ZnO + x Pr6O11+ 5 CoO (ZPC), (x = 0.1, 0.5 and 1.0) and sintered at 1300 and 1350 degrees C, were investigated. According to X-ray diffraction, several phases (ZnO, Pr2O3 and Pr2CoO4) are present when x = 1.0. Using Scanning Electron Microscopy, all of these compositions contain precipitates. These phases are important regarding the development of the microstructure and the electrical properties. The samples with x = 0.1 introduce the best nonohmic behavior (alpha = 9.0), however when x = 0.5 the electrical properties are highly degraded due to the small quantity of effective barriers. The density of superficial states N-IS and donor concentration Nd decreases with Pr6O11 addition. The decrease in the donor concentration is attributed to the annihilation of the donor defects according to the transformation of praseodymium oxides from Pr6O11 to Pr2O3.
publishDate 2010
dc.date.none.fl_str_mv 2010-01-01
2014-05-20T14:18:19Z
2014-05-20T14:18:19Z
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv http://dx.doi.org/10.1590/S1516-14392010000100008
Materials Research-ibero-american Journal of Materials. São Carlos: Universidade Federal de São Carlos (UFSCar), Dept Engenharia Materials, v. 13, n. 1, p. 29-34, 2010.
1516-1439
http://hdl.handle.net/11449/131704
10.1590/S1516-14392010000100008
S1516-14392010000100008
WOS:000276894200008
S1516-14392010000100008.pdf
url http://dx.doi.org/10.1590/S1516-14392010000100008
http://hdl.handle.net/11449/131704
identifier_str_mv Materials Research-ibero-american Journal of Materials. São Carlos: Universidade Federal de São Carlos (UFSCar), Dept Engenharia Materials, v. 13, n. 1, p. 29-34, 2010.
1516-1439
10.1590/S1516-14392010000100008
S1516-14392010000100008
WOS:000276894200008
S1516-14392010000100008.pdf
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv Materials Research-ibero-american Journal of Materials
1.103
0,398
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv 29-34
application/pdf
dc.publisher.none.fl_str_mv Universidade Federal de São Carlos (UFSCar), Dept Engenharia Materials
publisher.none.fl_str_mv Universidade Federal de São Carlos (UFSCar), Dept Engenharia Materials
dc.source.none.fl_str_mv Web of Science
reponame:Repositório Institucional da UNESP
instname:Universidade Estadual Paulista (UNESP)
instacron:UNESP
instname_str Universidade Estadual Paulista (UNESP)
instacron_str UNESP
institution UNESP
reponame_str Repositório Institucional da UNESP
collection Repositório Institucional da UNESP
repository.name.fl_str_mv Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)
repository.mail.fl_str_mv
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