Molecular simulations of the synthesis of periodic mesoporous silica phases at high surfactant concentrations
Autor(a) principal: | |
---|---|
Data de Publicação: | 2017 |
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/10773/33244 |
Resumo: | Molecular dynamics simulations of a coarse-grained model are used to study the formation mechanism of periodic mesoporous silica over a wide range of cationic surfactant concentrations. This follows up on an earlier study of systems with low surfactant concentrations. We started by studying the phase diagram of the surfactant-water system and found that our model shows good qualitative agreement with experiments with respect to the surfactant concentrations where various phases appear. We then considered the impact of silicate species upon the morphologies formed. We have found that even in concentrated surfactant systems --in the concentration range where pure surfactant solutions yield a liquid crystal phase -- the liquid-crystal templating mechanism is not viable because the preformed liquid crystal collapses as silica monomers are added into the solution. Upon the addition of silica dimers, a new phase-separated hexagonal array is formed. The preformed liquid crystals were found to be unstable in the presence of monomeric silicates. In addition, the silica dimer is found to be essential for mesoscale ordering at both low and high surfactant concentrations. Our results support the view that a cooperative interaction of anionic silica oligomers and cationic surfactants determines the mesostructure formation in the M41S family of materials. |
id |
RCAP_9e944813135b3b7feb71c19a5278f999 |
---|---|
oai_identifier_str |
oai:ria.ua.pt:10773/33244 |
network_acronym_str |
RCAP |
network_name_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository_id_str |
7160 |
spelling |
Molecular simulations of the synthesis of periodic mesoporous silica phases at high surfactant concentrationsMonomersOligomersSilicaMesostructuresSurfactantsMolecular dynamics simulations of a coarse-grained model are used to study the formation mechanism of periodic mesoporous silica over a wide range of cationic surfactant concentrations. This follows up on an earlier study of systems with low surfactant concentrations. We started by studying the phase diagram of the surfactant-water system and found that our model shows good qualitative agreement with experiments with respect to the surfactant concentrations where various phases appear. We then considered the impact of silicate species upon the morphologies formed. We have found that even in concentrated surfactant systems --in the concentration range where pure surfactant solutions yield a liquid crystal phase -- the liquid-crystal templating mechanism is not viable because the preformed liquid crystal collapses as silica monomers are added into the solution. Upon the addition of silica dimers, a new phase-separated hexagonal array is formed. The preformed liquid crystals were found to be unstable in the presence of monomeric silicates. In addition, the silica dimer is found to be essential for mesoscale ordering at both low and high surfactant concentrations. Our results support the view that a cooperative interaction of anionic silica oligomers and cationic surfactants determines the mesostructure formation in the M41S family of materials.American Chemical Society2022-02-22T13:40:35Z2017-03-02T00:00:00Z2017-03-02info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfapplication/pdfhttp://hdl.handle.net/10773/33244eng1932-744710.1021/acs.jpcc.6b09429Chien, Szu-ChiaPerez-Sanchez, GermánGomes, José R. B.Cordeiro, M. Natália D. S.Jorge, MiguelAuerbach, Scott M.Monson, Peter A.info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2024-02-22T12:03:44Zoai:ria.ua.pt:10773/33244Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T03:04:37.422127Repositório 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 |
Molecular simulations of the synthesis of periodic mesoporous silica phases at high surfactant concentrations |
title |
Molecular simulations of the synthesis of periodic mesoporous silica phases at high surfactant concentrations |
spellingShingle |
Molecular simulations of the synthesis of periodic mesoporous silica phases at high surfactant concentrations Chien, Szu-Chia Monomers Oligomers Silica Mesostructures Surfactants |
title_short |
Molecular simulations of the synthesis of periodic mesoporous silica phases at high surfactant concentrations |
title_full |
Molecular simulations of the synthesis of periodic mesoporous silica phases at high surfactant concentrations |
title_fullStr |
Molecular simulations of the synthesis of periodic mesoporous silica phases at high surfactant concentrations |
title_full_unstemmed |
Molecular simulations of the synthesis of periodic mesoporous silica phases at high surfactant concentrations |
title_sort |
Molecular simulations of the synthesis of periodic mesoporous silica phases at high surfactant concentrations |
author |
Chien, Szu-Chia |
author_facet |
Chien, Szu-Chia Perez-Sanchez, Germán Gomes, José R. B. Cordeiro, M. Natália D. S. Jorge, Miguel Auerbach, Scott M. Monson, Peter A. |
author_role |
author |
author2 |
Perez-Sanchez, Germán Gomes, José R. B. Cordeiro, M. Natália D. S. Jorge, Miguel Auerbach, Scott M. Monson, Peter A. |
author2_role |
author author author author author author |
dc.contributor.author.fl_str_mv |
Chien, Szu-Chia Perez-Sanchez, Germán Gomes, José R. B. Cordeiro, M. Natália D. S. Jorge, Miguel Auerbach, Scott M. Monson, Peter A. |
dc.subject.por.fl_str_mv |
Monomers Oligomers Silica Mesostructures Surfactants |
topic |
Monomers Oligomers Silica Mesostructures Surfactants |
description |
Molecular dynamics simulations of a coarse-grained model are used to study the formation mechanism of periodic mesoporous silica over a wide range of cationic surfactant concentrations. This follows up on an earlier study of systems with low surfactant concentrations. We started by studying the phase diagram of the surfactant-water system and found that our model shows good qualitative agreement with experiments with respect to the surfactant concentrations where various phases appear. We then considered the impact of silicate species upon the morphologies formed. We have found that even in concentrated surfactant systems --in the concentration range where pure surfactant solutions yield a liquid crystal phase -- the liquid-crystal templating mechanism is not viable because the preformed liquid crystal collapses as silica monomers are added into the solution. Upon the addition of silica dimers, a new phase-separated hexagonal array is formed. The preformed liquid crystals were found to be unstable in the presence of monomeric silicates. In addition, the silica dimer is found to be essential for mesoscale ordering at both low and high surfactant concentrations. Our results support the view that a cooperative interaction of anionic silica oligomers and cationic surfactants determines the mesostructure formation in the M41S family of materials. |
publishDate |
2017 |
dc.date.none.fl_str_mv |
2017-03-02T00:00:00Z 2017-03-02 2022-02-22T13:40:35Z |
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/10773/33244 |
url |
http://hdl.handle.net/10773/33244 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
1932-7447 10.1021/acs.jpcc.6b09429 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
American Chemical Society |
publisher.none.fl_str_mv |
American Chemical Society |
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 |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
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 |
repository.mail.fl_str_mv |
|
_version_ |
1799137701253873664 |