Spatial distribution of organic functional groups supported on mesoporous silica nanoparticles: a study by conventional and DNP-enhanced 29Si solid-state NMR
Royal Society of Chemistry
Is Version Of
Solid-state NMR spectroscopy, both conventional and dynamic nuclear polarization (DNP)-enhanced, was employed to study the spatial distribution of organic functional groups attached to the surface of mesoporous silica nanoparticles via co-condensation and grafting. The most revealing information was provided by DNP-enhanced two-dimensional 29Si–29Si correlation measurements, which unambiguously showed that post-synthesis grafting leads to a more homogeneous dispersion of propyl and mercaptopropyl functionalities than co-condensation. During the anhydrous grafting process, the organosilane precursors do not self-condense and are unlikely to bond to the silica surface in close proximity (less than 4 Å) due to the limited availability of suitably arranged hydroxyl groups.
This is a manuscript of an article published as Kobayashi, Takeshi, Dilini Singappuli-Arachchige, Zhuoran Wang, Igor I. Slowing, and Marek Pruski. "Spatial distribution of organic functional groups supported on mesoporous silica nanoparticles: A study by conventional and DNP-enhanced 29 Si solid-state NMR." Physical Chemistry Chemical Physics 19, no. 3 (2017): 1781-1789. DOI: 10.1039/C6CP07642D. Copyright 2022 The Royal Society of Chemistry. Posted with permission.