| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 73892 | Microporous and Mesoporous Materials | 2012 | 5 Pages |
Based on the quantitative cross-polarization (QCP) and direct excitation (DE) solid-state 29Si NMR techniques, a novel scheme for quantitative characterization of silica structures is developed. The QCP technique is used to determine the ratio between geminal silanol (Q2) and single silanol (Q3), while the DE technique with a small number of scans is used to determine the ratio of Q3 and siloxane (Q4). As a result, the proportions of Q2, Q3 and Q4 groups in mesoporous SBA-15 silica are determined and the scheme saves considerable experimental time.
Graphical abstractReciprocity relation between the dynamics of cross polarization (CP) and cross depolarization (CDP) for a single silanol (Q3) group of SBA-15.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The molar ratios of Q2, Q3 and Q4 groups in mesoporous SBA-15 silica are determined by a novel NMR method. ► Quantitative cross-polarization and direct excitation 29Si NMR is successfully applied to silica containing molecules. ► The quantitative scheme saves considerable experimental time.
