Template-Free Self-Assembly of Mesoporous Organosilicas
| Autor: | Mobae Afeworki, Brian K. Peterson, David C. Calabro, Manesh Gopinadhan, Quanchang Li, Meghan L. Nines Kochersperger, Michael Sansone, Robert J. Colby, Simon C. Weston, Nicole Callen |
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| Rok vydání: | 2018 |
| Předmět: |
Template free
Materials science Pore diameter General Chemical Engineering 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Mesoporous organosilica Chemical engineering Volume (thermodynamics) Materials Chemistry High surface area Self-assembly 0210 nano-technology Porosity Mesoporous material |
| Zdroj: | Chemistry of Materials. 30:2218-2228 |
| ISSN: | 1520-5002 0897-4756 |
| DOI: | 10.1021/acs.chemmater.7b04480 |
| Popis: | Using a known organosilane building block (1,1,3,3,5,5-hexaethoxy-1,3,5-trisilacyclohexane), materials with unexpectedly high surface area (>1200 m2/g) and porosity with narrow pore-size distributions were synthesized in the total absence of pore-templating agents. The properties of these mesoporous organosilicas (MOS), closely resembling those of surfactant-templated mesoporous silicas, are found to vary over a wide range depending on synthesis gel pH and gelation temperature and time. Considerable microporosity is observed at short 90 °C gelation times at pH 12.5, which diminishes to a very minor component of the porosity at times > 23 h. Under the gelation conditions used here (90 °C, pH 12.5), pore volume and pore diameter rise sharply with time, ultimately leveling off at 1.2 cm3/g and 70 A at times > 70 h. This building block is shown to be stable in acidic gels but undergoes gradual ring opening at gelation temperatures and times in excess of “standard” conditions employed for alkaline gels.The syn... |
| Databáze: | OpenAIRE |
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