Mechanosynthesis and electrical conductivity of undoped and calcium-substituted GdAlO3 perovskites
Autor(a) principal: | |
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Data de Publicação: | 2023 |
Outros Autores: | , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10773/39401 |
Resumo: | Gadolinium aluminate (GdAlO3) and its calcium-substituted derivates (Gd1-xCaxAlO3-δ; x = 0.05, 0.10 and 0.15) are prepared via one-step mechanochemical processing of simple oxide precursors at ambient temperature. The mechanochemical reaction is accompanied by Gd2O3 phase transformation. The as-prepared and sintered materials are characterized by X-ray diffraction and scanning electron microscopy. Sintering at 1450°C resulted in relatively porous ceramics (with density <90% of theoretical value) except Gd0.85Ca0.15AlO3-δ. The electrical conductivity of the sintered samples was investigated by impedance spectroscopy at 350-1000°C in air. Undoped GdAlO3 ceramics exhibit low conductivity, ~10-6 S/cm at 800°C. Acceptor-type substitution of 5 at.% of gadolinium by calcium results in ~3 orders of magnitude increase in both total and bulk conductivity associated with a substantial enhancement in oxygen-ionic transport. Further doping has a limited effect on the electrical transport properties, and electrical conductivity remains nearly composition-independent in the range x = 0.05-0.15. Grain boundaries are demonstrated to have a significant contribution to the total resistivity of prepared calcium-substituted Gd1-xCaxAlO3-δ ceramics with grain sizes in the range of 1.1-1.5 μm. |
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Mechanosynthesis and electrical conductivity of undoped and calcium-substituted GdAlO3 perovskitesGadolinium aluminateMechanosynthesisPhase transformationElectrical conductivityPerovskiteGadolinium aluminate (GdAlO3) and its calcium-substituted derivates (Gd1-xCaxAlO3-δ; x = 0.05, 0.10 and 0.15) are prepared via one-step mechanochemical processing of simple oxide precursors at ambient temperature. The mechanochemical reaction is accompanied by Gd2O3 phase transformation. The as-prepared and sintered materials are characterized by X-ray diffraction and scanning electron microscopy. Sintering at 1450°C resulted in relatively porous ceramics (with density <90% of theoretical value) except Gd0.85Ca0.15AlO3-δ. The electrical conductivity of the sintered samples was investigated by impedance spectroscopy at 350-1000°C in air. Undoped GdAlO3 ceramics exhibit low conductivity, ~10-6 S/cm at 800°C. Acceptor-type substitution of 5 at.% of gadolinium by calcium results in ~3 orders of magnitude increase in both total and bulk conductivity associated with a substantial enhancement in oxygen-ionic transport. Further doping has a limited effect on the electrical transport properties, and electrical conductivity remains nearly composition-independent in the range x = 0.05-0.15. Grain boundaries are demonstrated to have a significant contribution to the total resistivity of prepared calcium-substituted Gd1-xCaxAlO3-δ ceramics with grain sizes in the range of 1.1-1.5 μm.Elsevier2025-11-25T00:00:00Z2023-11-25T00:00:00Z2023-11-25info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/10773/39401eng0925-838810.1016/j.jallcom.2023.171374Fabián, MartinArias-Serrano, Blanca I.Briančin, JaroslavYaremchenko, Alekseyinfo:eu-repo/semantics/embargoedAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2024-02-22T12:17:03Zoai:ria.ua.pt:10773/39401Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T03:09:37.710395Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Mechanosynthesis and electrical conductivity of undoped and calcium-substituted GdAlO3 perovskites |
title |
Mechanosynthesis and electrical conductivity of undoped and calcium-substituted GdAlO3 perovskites |
spellingShingle |
Mechanosynthesis and electrical conductivity of undoped and calcium-substituted GdAlO3 perovskites Fabián, Martin Gadolinium aluminate Mechanosynthesis Phase transformation Electrical conductivity Perovskite |
title_short |
Mechanosynthesis and electrical conductivity of undoped and calcium-substituted GdAlO3 perovskites |
title_full |
Mechanosynthesis and electrical conductivity of undoped and calcium-substituted GdAlO3 perovskites |
title_fullStr |
Mechanosynthesis and electrical conductivity of undoped and calcium-substituted GdAlO3 perovskites |
title_full_unstemmed |
Mechanosynthesis and electrical conductivity of undoped and calcium-substituted GdAlO3 perovskites |
title_sort |
Mechanosynthesis and electrical conductivity of undoped and calcium-substituted GdAlO3 perovskites |
author |
Fabián, Martin |
author_facet |
Fabián, Martin Arias-Serrano, Blanca I. Briančin, Jaroslav Yaremchenko, Aleksey |
author_role |
author |
author2 |
Arias-Serrano, Blanca I. Briančin, Jaroslav Yaremchenko, Aleksey |
author2_role |
author author author |
dc.contributor.author.fl_str_mv |
Fabián, Martin Arias-Serrano, Blanca I. Briančin, Jaroslav Yaremchenko, Aleksey |
dc.subject.por.fl_str_mv |
Gadolinium aluminate Mechanosynthesis Phase transformation Electrical conductivity Perovskite |
topic |
Gadolinium aluminate Mechanosynthesis Phase transformation Electrical conductivity Perovskite |
description |
Gadolinium aluminate (GdAlO3) and its calcium-substituted derivates (Gd1-xCaxAlO3-δ; x = 0.05, 0.10 and 0.15) are prepared via one-step mechanochemical processing of simple oxide precursors at ambient temperature. The mechanochemical reaction is accompanied by Gd2O3 phase transformation. The as-prepared and sintered materials are characterized by X-ray diffraction and scanning electron microscopy. Sintering at 1450°C resulted in relatively porous ceramics (with density <90% of theoretical value) except Gd0.85Ca0.15AlO3-δ. The electrical conductivity of the sintered samples was investigated by impedance spectroscopy at 350-1000°C in air. Undoped GdAlO3 ceramics exhibit low conductivity, ~10-6 S/cm at 800°C. Acceptor-type substitution of 5 at.% of gadolinium by calcium results in ~3 orders of magnitude increase in both total and bulk conductivity associated with a substantial enhancement in oxygen-ionic transport. Further doping has a limited effect on the electrical transport properties, and electrical conductivity remains nearly composition-independent in the range x = 0.05-0.15. Grain boundaries are demonstrated to have a significant contribution to the total resistivity of prepared calcium-substituted Gd1-xCaxAlO3-δ ceramics with grain sizes in the range of 1.1-1.5 μm. |
publishDate |
2023 |
dc.date.none.fl_str_mv |
2023-11-25T00:00:00Z 2023-11-25 2025-11-25T00:00:00Z |
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://hdl.handle.net/10773/39401 |
url |
http://hdl.handle.net/10773/39401 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
0925-8388 10.1016/j.jallcom.2023.171374 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/embargoedAccess |
eu_rights_str_mv |
embargoedAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier |
publisher.none.fl_str_mv |
Elsevier |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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1799137746488393728 |