Theoretical Study of the Adsorption of 2-Propanol onto Silica Surfaces on the Basis of and Density Functional Calculations
The adsorptive interactions of 2-propanol (2-PrOH) molecules with silica surfaces were investigated using ab initio and density functional calculations. Two cluster models of silica were chosen to represent the terminal ≡SiOH groups and the siloxane bridges ≡Si–(O) 2 –Si≡ on the silica surface. The...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
SAGE Publications
2009-04-01
|
| Series: | Adsorption Science & Technology |
| Online Access: | https://doi.org/10.1260/026361709789868884 |
| _version_ | 1797285072110354432 |
|---|---|
| author | Mariam R. Abdallah Muhammad A. Hasan Mohamed I. Zaki |
| author_facet | Mariam R. Abdallah Muhammad A. Hasan Mohamed I. Zaki |
| author_sort | Mariam R. Abdallah |
| collection | DOAJ |
| description | The adsorptive interactions of 2-propanol (2-PrOH) molecules with silica surfaces were investigated using ab initio and density functional calculations. Two cluster models of silica were chosen to represent the terminal ≡SiOH groups and the siloxane bridges ≡Si–(O) 2 –Si≡ on the silica surface. The Hartree–Fock (HF) and Density Functional Theory (DFT) approaches, employing a 6–31G(d) basis set, were used to calculate the geometries, electronic structures, vibrational frequencies and adsorption energies of the adsorption complexes formed. The calculated adsorption energies were corrected for zero-point vibrational energies (ZPVE) and basis set superposition errors (BSSE). The results favoured a most likely surface configuration for the physisorbed species in which 2-PrOH molecules are bound to exposed silanol groups via two hydrogen bonds, with the alcoholic –OH group acting simultaneously as a proton acceptor and donor. Moreover, bonding of 2-PrOH with strained surface siloxane bridges (≡Si–O–Si≡) was shown to lead to chemisorption of the alcohol molecule. These findings have been shown to help interpreting reported infrared spectroscopic results of in-situ experimental studies. |
| first_indexed | 2024-03-07T17:56:57Z |
| format | Article |
| id | doaj.art-968a4295ad404fde9928c0badece86e4 |
| institution | Directory Open Access Journal |
| issn | 0263-6174 2048-4038 |
| language | English |
| last_indexed | 2024-03-07T17:56:57Z |
| publishDate | 2009-04-01 |
| publisher | SAGE Publications |
| record_format | Article |
| series | Adsorption Science & Technology |
| spelling | doaj.art-968a4295ad404fde9928c0badece86e42024-03-02T11:48:41ZengSAGE PublicationsAdsorption Science & Technology0263-61742048-40382009-04-012710.1260/026361709789868884Theoretical Study of the Adsorption of 2-Propanol onto Silica Surfaces on the Basis of and Density Functional CalculationsMariam R. Abdallah0Muhammad A. Hasan1Mohamed I. Zaki2 Chemistry Department, Faculty of Science, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait Chemistry Department, Faculty of Science, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait Chemistry Department, Faculty of Science, Minia University, El-Minia 61519, EgyptThe adsorptive interactions of 2-propanol (2-PrOH) molecules with silica surfaces were investigated using ab initio and density functional calculations. Two cluster models of silica were chosen to represent the terminal ≡SiOH groups and the siloxane bridges ≡Si–(O) 2 –Si≡ on the silica surface. The Hartree–Fock (HF) and Density Functional Theory (DFT) approaches, employing a 6–31G(d) basis set, were used to calculate the geometries, electronic structures, vibrational frequencies and adsorption energies of the adsorption complexes formed. The calculated adsorption energies were corrected for zero-point vibrational energies (ZPVE) and basis set superposition errors (BSSE). The results favoured a most likely surface configuration for the physisorbed species in which 2-PrOH molecules are bound to exposed silanol groups via two hydrogen bonds, with the alcoholic –OH group acting simultaneously as a proton acceptor and donor. Moreover, bonding of 2-PrOH with strained surface siloxane bridges (≡Si–O–Si≡) was shown to lead to chemisorption of the alcohol molecule. These findings have been shown to help interpreting reported infrared spectroscopic results of in-situ experimental studies.https://doi.org/10.1260/026361709789868884 |
| spellingShingle | Mariam R. Abdallah Muhammad A. Hasan Mohamed I. Zaki Theoretical Study of the Adsorption of 2-Propanol onto Silica Surfaces on the Basis of and Density Functional Calculations Adsorption Science & Technology |
| title | Theoretical Study of the Adsorption of 2-Propanol onto Silica Surfaces on the Basis of and Density Functional Calculations |
| title_full | Theoretical Study of the Adsorption of 2-Propanol onto Silica Surfaces on the Basis of and Density Functional Calculations |
| title_fullStr | Theoretical Study of the Adsorption of 2-Propanol onto Silica Surfaces on the Basis of and Density Functional Calculations |
| title_full_unstemmed | Theoretical Study of the Adsorption of 2-Propanol onto Silica Surfaces on the Basis of and Density Functional Calculations |
| title_short | Theoretical Study of the Adsorption of 2-Propanol onto Silica Surfaces on the Basis of and Density Functional Calculations |
| title_sort | theoretical study of the adsorption of 2 propanol onto silica surfaces on the basis of and density functional calculations |
| url | https://doi.org/10.1260/026361709789868884 |
| work_keys_str_mv | AT mariamrabdallah theoreticalstudyoftheadsorptionof2propanolontosilicasurfacesonthebasisofanddensityfunctionalcalculations AT muhammadahasan theoreticalstudyoftheadsorptionof2propanolontosilicasurfacesonthebasisofanddensityfunctionalcalculations AT mohamedizaki theoreticalstudyoftheadsorptionof2propanolontosilicasurfacesonthebasisofanddensityfunctionalcalculations |