Structural characterization of mullites synthesized by thermal decomposition of topaz

Detalhes bibliográficos
Autor(a) principal: Soares,Robson de Miranda
Data de Publicação: 2007
Outros Autores: Sabioni,Antônio Claret Soares, Resck,Inês Sabioni, Falcomer,Viviane Aparecida Silva, Dias,José Alves, Silva,Naira Machado da, Menezes,Sônia Maria Cabral de, Costa,Geraldo Magela da
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Materials research (São Carlos. Online)
Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392007000100016
Resumo: The structure of mullite obtained by thermal decomposition of topaz at 1340 °C and after additional thermal treatment at 1600 °C was characterized by 29Si and 27Al MAS NMR spectroscopy and x ray diffraction. No amorphous phase was detected by these techniques. The 29Si MAS NMR spectra of the mullite samples showed four resonance peaks at -81, -86, -90 and -94 ppm. The peak at -81 ppm corresponded to silicon near oxygen vacancies in the mullite structure. The peak at 86 ppm was related to a sillimanite-type site and was the major contribution, ranging from 42 to 50%. The two other peaks, at -90.0 ppm and -94 ppm, were interpreted as resulting from rearrangements of the sillimanite-type site by the replacement of AlO4 by SiO4 tetrahedra16. The 27Al MAS NMR data of the two samples exhibited three different peaks, two of which were attributed to tetrahedral sites at 40 -45 and 63 -67 ppm, while the third was assigned to an octahedral site at about -6 ppm. The ratio of tetrahedral to octahedral aluminum sites was found to depend on the temperature applied during the preparation of the mullite and was higher at 1600 °C.
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spelling Structural characterization of mullites synthesized by thermal decomposition of topazmullite synthesistopazcharacterization27Al and 29Si MAS NMR, XRDThe structure of mullite obtained by thermal decomposition of topaz at 1340 °C and after additional thermal treatment at 1600 °C was characterized by 29Si and 27Al MAS NMR spectroscopy and x ray diffraction. No amorphous phase was detected by these techniques. The 29Si MAS NMR spectra of the mullite samples showed four resonance peaks at -81, -86, -90 and -94 ppm. The peak at -81 ppm corresponded to silicon near oxygen vacancies in the mullite structure. The peak at 86 ppm was related to a sillimanite-type site and was the major contribution, ranging from 42 to 50%. The two other peaks, at -90.0 ppm and -94 ppm, were interpreted as resulting from rearrangements of the sillimanite-type site by the replacement of AlO4 by SiO4 tetrahedra16. The 27Al MAS NMR data of the two samples exhibited three different peaks, two of which were attributed to tetrahedral sites at 40 -45 and 63 -67 ppm, while the third was assigned to an octahedral site at about -6 ppm. The ratio of tetrahedral to octahedral aluminum sites was found to depend on the temperature applied during the preparation of the mullite and was higher at 1600 °C.ABM, ABC, ABPol2007-03-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392007000100016Materials Research v.10 n.1 2007reponame:Materials research (São Carlos. Online)instname:Universidade Federal de São Carlos (UFSCAR)instacron:ABM ABC ABPOL10.1590/S1516-14392007000100016info:eu-repo/semantics/openAccessSoares,Robson de MirandaSabioni,Antônio Claret SoaresResck,Inês SabioniFalcomer,Viviane Aparecida SilvaDias,José AlvesSilva,Naira Machado daMenezes,Sônia Maria Cabral deCosta,Geraldo Magela daeng2007-05-03T00:00:00Zoai:scielo:S1516-14392007000100016Revistahttp://www.scielo.br/mrPUBhttps://old.scielo.br/oai/scielo-oai.phpdedz@power.ufscar.br1980-53731516-1439opendoar:2007-05-03T00:00Materials research (São Carlos. Online) - Universidade Federal de São Carlos (UFSCAR)false
dc.title.none.fl_str_mv Structural characterization of mullites synthesized by thermal decomposition of topaz
title Structural characterization of mullites synthesized by thermal decomposition of topaz
spellingShingle Structural characterization of mullites synthesized by thermal decomposition of topaz
Soares,Robson de Miranda
mullite synthesis
topaz
characterization
27Al and 29Si MAS NMR, XRD
title_short Structural characterization of mullites synthesized by thermal decomposition of topaz
title_full Structural characterization of mullites synthesized by thermal decomposition of topaz
title_fullStr Structural characterization of mullites synthesized by thermal decomposition of topaz
title_full_unstemmed Structural characterization of mullites synthesized by thermal decomposition of topaz
title_sort Structural characterization of mullites synthesized by thermal decomposition of topaz
author Soares,Robson de Miranda
author_facet Soares,Robson de Miranda
Sabioni,Antônio Claret Soares
Resck,Inês Sabioni
Falcomer,Viviane Aparecida Silva
Dias,José Alves
Silva,Naira Machado da
Menezes,Sônia Maria Cabral de
Costa,Geraldo Magela da
author_role author
author2 Sabioni,Antônio Claret Soares
Resck,Inês Sabioni
Falcomer,Viviane Aparecida Silva
Dias,José Alves
Silva,Naira Machado da
Menezes,Sônia Maria Cabral de
Costa,Geraldo Magela da
author2_role author
author
author
author
author
author
author
dc.contributor.author.fl_str_mv Soares,Robson de Miranda
Sabioni,Antônio Claret Soares
Resck,Inês Sabioni
Falcomer,Viviane Aparecida Silva
Dias,José Alves
Silva,Naira Machado da
Menezes,Sônia Maria Cabral de
Costa,Geraldo Magela da
dc.subject.por.fl_str_mv mullite synthesis
topaz
characterization
27Al and 29Si MAS NMR, XRD
topic mullite synthesis
topaz
characterization
27Al and 29Si MAS NMR, XRD
description The structure of mullite obtained by thermal decomposition of topaz at 1340 °C and after additional thermal treatment at 1600 °C was characterized by 29Si and 27Al MAS NMR spectroscopy and x ray diffraction. No amorphous phase was detected by these techniques. The 29Si MAS NMR spectra of the mullite samples showed four resonance peaks at -81, -86, -90 and -94 ppm. The peak at -81 ppm corresponded to silicon near oxygen vacancies in the mullite structure. The peak at 86 ppm was related to a sillimanite-type site and was the major contribution, ranging from 42 to 50%. The two other peaks, at -90.0 ppm and -94 ppm, were interpreted as resulting from rearrangements of the sillimanite-type site by the replacement of AlO4 by SiO4 tetrahedra16. The 27Al MAS NMR data of the two samples exhibited three different peaks, two of which were attributed to tetrahedral sites at 40 -45 and 63 -67 ppm, while the third was assigned to an octahedral site at about -6 ppm. The ratio of tetrahedral to octahedral aluminum sites was found to depend on the temperature applied during the preparation of the mullite and was higher at 1600 °C.
publishDate 2007
dc.date.none.fl_str_mv 2007-03-01
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392007000100016
url http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392007000100016
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv 10.1590/S1516-14392007000100016
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv text/html
dc.publisher.none.fl_str_mv ABM, ABC, ABPol
publisher.none.fl_str_mv ABM, ABC, ABPol
dc.source.none.fl_str_mv Materials Research v.10 n.1 2007
reponame:Materials research (São Carlos. Online)
instname:Universidade Federal de São Carlos (UFSCAR)
instacron:ABM ABC ABPOL
instname_str Universidade Federal de São Carlos (UFSCAR)
instacron_str ABM ABC ABPOL
institution ABM ABC ABPOL
reponame_str Materials research (São Carlos. Online)
collection Materials research (São Carlos. Online)
repository.name.fl_str_mv Materials research (São Carlos. Online) - Universidade Federal de São Carlos (UFSCAR)
repository.mail.fl_str_mv dedz@power.ufscar.br
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