Defect Sites in Zeolites: Origin and Healing
Abstract This paper deals with the synthesis conditions–defect formation relationship in zeolites. Silicalite‐1 (MFI‐type) is used as a model material. Samples synthesized from a system with high basicity (at 100 °C), a system with moderate basicity (at 150 °C), and a fluoride‐containing system in n...
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| Format: | Article |
| Language: | English |
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Wiley
2022-02-01
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| Series: | Advanced Science |
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| Online Access: | https://doi.org/10.1002/advs.202104414 |
| _version_ | 1828142189140508672 |
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| author | Ana Palčić Simona Moldovan Hussein El Siblani Aurelie Vicente Valentin Valtchev |
| author_facet | Ana Palčić Simona Moldovan Hussein El Siblani Aurelie Vicente Valentin Valtchev |
| author_sort | Ana Palčić |
| collection | DOAJ |
| description | Abstract This paper deals with the synthesis conditions–defect formation relationship in zeolites. Silicalite‐1 (MFI‐type) is used as a model material. Samples synthesized from a system with high basicity (at 100 °C), a system with moderate basicity (at 150 °C), and a fluoride‐containing system in neutral medium (at 170 °C) are compared. Well‐crystallized materials with sizes ≈0.1, 1–10, and 30–40 µm are obtained. The samples are analyzed by complementary methods providing information on the short‐ and long‐range order in the zeolite framework. A strong correlation between the number of point defects in the zeolite framework and preparation conditions is established. Silicalite‐1 synthesized under mild synthesis conditions from a highly basic system exhibits a larger number of framework defects and thus low hydrophobicity. Further, the calcined samples are subjected to aluminum and silicon incorporation by postsynthesis treatment. The Al/Si incorporation in the zeolite framework and its impact on the physicochemical properties is studied by XRD, TEM/SEM, solid‐state NMR, FTIR, and thermogravimetric analyses. The defects healing as a function of the number of point defects in the initial material and zeolite crystal size is evaluated. The results of this study will serve for fine‐tuning zeolite properties by in situ and postsynthesis methods. |
| first_indexed | 2024-04-11T19:36:40Z |
| format | Article |
| id | doaj.art-ceceb94a3dce4843ac899afba351a3a1 |
| institution | Directory Open Access Journal |
| issn | 2198-3844 |
| language | English |
| last_indexed | 2024-04-11T19:36:40Z |
| publishDate | 2022-02-01 |
| publisher | Wiley |
| record_format | Article |
| series | Advanced Science |
| spelling | doaj.art-ceceb94a3dce4843ac899afba351a3a12022-12-22T04:06:50ZengWileyAdvanced Science2198-38442022-02-0194n/an/a10.1002/advs.202104414Defect Sites in Zeolites: Origin and HealingAna Palčić0Simona Moldovan1Hussein El Siblani2Aurelie Vicente3Valentin Valtchev4Ruđer Bošković Institute Division of Materials Chemistry Laboratory for Synthesis of New Materials Bijenička cesta 54 Zagreb 10000 CroatiaInstitut des Sciences Appliquées de Rouen Rouen University Groupe de Physique des Matériaux (GPM) avenue de l'Université, BP12, Saint‐Étienne‐du‐Rouvray Cedex Rouen 76801 FranceNormandie Université ENSICAEN UNICAEN CNRS Laboratoire Catalyse et Spectrochimie 6 Boulevard Maréchal Juin Caen 14050 FranceNormandie Université ENSICAEN UNICAEN CNRS Laboratoire Catalyse et Spectrochimie 6 Boulevard Maréchal Juin Caen 14050 FranceNormandie Université ENSICAEN UNICAEN CNRS Laboratoire Catalyse et Spectrochimie 6 Boulevard Maréchal Juin Caen 14050 FranceAbstract This paper deals with the synthesis conditions–defect formation relationship in zeolites. Silicalite‐1 (MFI‐type) is used as a model material. Samples synthesized from a system with high basicity (at 100 °C), a system with moderate basicity (at 150 °C), and a fluoride‐containing system in neutral medium (at 170 °C) are compared. Well‐crystallized materials with sizes ≈0.1, 1–10, and 30–40 µm are obtained. The samples are analyzed by complementary methods providing information on the short‐ and long‐range order in the zeolite framework. A strong correlation between the number of point defects in the zeolite framework and preparation conditions is established. Silicalite‐1 synthesized under mild synthesis conditions from a highly basic system exhibits a larger number of framework defects and thus low hydrophobicity. Further, the calcined samples are subjected to aluminum and silicon incorporation by postsynthesis treatment. The Al/Si incorporation in the zeolite framework and its impact on the physicochemical properties is studied by XRD, TEM/SEM, solid‐state NMR, FTIR, and thermogravimetric analyses. The defects healing as a function of the number of point defects in the initial material and zeolite crystal size is evaluated. The results of this study will serve for fine‐tuning zeolite properties by in situ and postsynthesis methods.https://doi.org/10.1002/advs.202104414Al/Si incorporationdefect sitespostsynthesis treatmentsilanolszeolites |
| spellingShingle | Ana Palčić Simona Moldovan Hussein El Siblani Aurelie Vicente Valentin Valtchev Defect Sites in Zeolites: Origin and Healing Advanced Science Al/Si incorporation defect sites postsynthesis treatment silanols zeolites |
| title | Defect Sites in Zeolites: Origin and Healing |
| title_full | Defect Sites in Zeolites: Origin and Healing |
| title_fullStr | Defect Sites in Zeolites: Origin and Healing |
| title_full_unstemmed | Defect Sites in Zeolites: Origin and Healing |
| title_short | Defect Sites in Zeolites: Origin and Healing |
| title_sort | defect sites in zeolites origin and healing |
| topic | Al/Si incorporation defect sites postsynthesis treatment silanols zeolites |
| url | https://doi.org/10.1002/advs.202104414 |
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