Liquid-state Si-29 NMR study on the chemical kinetics of Stober synthesis
文献类型：期刊论文
| 作者 | Liu, RL; Xu, Y; Li, ZH; Wu, D; Sun, YH; Gao, HC; Yuan, HZ; Deng, F |
| 刊名 | ACTA CHIMICA SINICA
 |
| 出版日期 | 2004-01-14 |
| 卷号 | 62期号:1页码:22-27 |
| 关键词 | kinetics Si-29 NMR Stober synthesis sol-gel |
| 英文摘要 | Stober syntheses, the ammonia-catalyzed reactions of tetraetboxysilane with water in low molecular weight (MW) alcohols, produce highly monodisperse, spherical silica nanoparticles with size ranging from 5 to 2000 nm. It is the initial hydrolysis and polycondensation process that have been investigated by liquid-state Si-29 NMR. We found that the intermediate species was Q(0)(1); the reaction equation of the rate-determining step was r = k(h) [TEOS] . [NH3](0.457)[H2O](0.051); the constant value was k(h) = 7.32 x 10(-3) mol(-0.5) . dm(1.5) . min(-1) (T=25 degreesC). In the meantime, the reaction rate constant values of those non-rate-determining steps by using the transition state theory were calculated, and the values of the activation energy and the Arrhenius constant were also derived. The results suggested that the reaction rates of the hydrolysis and condensation become faster with increasing the temperature, and the rate constant value of the rate-determining step increases larger than that of non-rate-determining step, indicating that high temperature is more favorable for the hydrolysis of TEOS. The molar ratios of H2O/TEOS and NH3/TEOS were adjusted to examine the effect of H2O and NH3 and we found that the reaction rates of hydrolysis and condensation of TEOS largely depended on the concentration of NH3 but not that of H2O. |
| WOS标题词 | Science & Technology ; Physical Sciences |
| 类目[WOS] | Chemistry, Multidisciplinary |
| 研究领域[WOS] | Chemistry |
| 关键词[WOS] | CATALYZED-HYDROLYSIS ; SILICA PARTICLES ; STEADY-STATE ; GROWTH ; RANGE ; ETHYL |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000187998100005 |
| 公开日期 | 2015-12-08 |
| 源URL | [http://ir.wipm.ac.cn/handle/112942/8992]  |
| 专题 | 武汉物理与数学研究所_2011年以前论文发表（包括2011年） |
| 作者单位 | 1.Chinese Acad Sci, Shanxi Inst Coal Chem, State Key Lab Coal Convers, Taiyuan 030001, Peoples R China 2.Chinese Acad Sci, Wuhan Inst Phys & Math, State Key Lab Magnet Resonance & Atom & Mol Phys, Wuhan 430071, Peoples R China |
| 推荐引用方式 GB/T 7714 | Liu, RL,Xu, Y,Li, ZH,et al. Liquid-state Si-29 NMR study on the chemical kinetics of Stober synthesis[J]. ACTA CHIMICA SINICA,2004,62(1):22-27. |
| APA | Liu, RL.,Xu, Y.,Li, ZH.,Wu, D.,Sun, YH.,...&Deng, F.(2004).Liquid-state Si-29 NMR study on the chemical kinetics of Stober synthesis.ACTA CHIMICA SINICA,62(1),22-27. |
| MLA | Liu, RL,et al."Liquid-state Si-29 NMR study on the chemical kinetics of Stober synthesis".ACTA CHIMICA SINICA 62.1(2004):22-27. |
入库方式： OAI收割
来源：武汉物理与数学研究所
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