Structural characterization of mullites synthesized by thermal decomposition of topaz
Autor(a) principal: | |
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Data de Publicação: | 2007 |
Outros Autores: | , , , , , , |
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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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 |
_version_ |
1754212658517639168 |