Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany.
J Colloid Interface Sci. 2012 Feb 15;368(1):208-19. doi: 10.1016/j.jcis.2011.10.070. Epub 2011 Nov 10.
The synthesis of Stöber silica particles as basis for redox modifications is optimized for desired properties, in particular diameter in a wide sub-micrometer range, spherical shape, monodispersity, the absence of porosity, and aggregation free isolability for characterization and later covalent modification. The materials are characterized by SEM, DLS, nitrogen sorption isotherms, helium as well as Gay-Lussac (water) pycnometry, and DRIFT spectroscopy. Particles with diameters between approximately 50 and 800 nm are obtained by varying the concentrations of the reagents and reactants, the type of solvent as well as the temperature. The use of high water concentrations and post-synthetic calcination at 600 °C results in silica particles that can be considered as nonporous with respect to the size of the active molecules to be immobilized. The effect of reaction temperature on size distribution is identified. Low polydispersity is achieved by performing the reaction in a temperature range in which a change in temperature has only a weak or no effect on the final particle diameter. Upon optimization of the sol-gel process, the shape of the particles is still spherical. The agreement between experimental and geometric data is within the expected precision of the characterization techniques.
Stöber 二氧化硅颗粒的合成被优化以获得所需的性质，特别是在较宽的亚微米范围内的直径、球形、单分散性、无孔隙率和无聚集的可分离性，以用于表征和随后的共价修饰。这些材料通过 SEM、DLS、氮气吸附等温线、氦气和 Gay-Lussac（水）比重瓶以及 DRIFT 光谱进行表征。通过改变试剂和反应物的浓度、溶剂的类型以及温度，可以获得直径在约 50 至 800nm 之间的颗粒。使用高水浓度和 600°C 的后合成煅烧导致可以认为对于要固定的活性分子的尺寸而言，二氧化硅颗粒是无孔的。确定了反应温度对粒径分布的影响。通过在温度范围内进行反应，可以实现低多分散性，其中温度变化对最终颗粒直径的影响较弱或没有影响。在优化溶胶-凝胶工艺后，颗粒的形状仍然是球形。实验数据和几何数据之间的一致性在表征技术的预期精度范围内。
