Wilhelm P, Stephan D
Lehrstuhl für Bauchemie, Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85747 Garching, Germany.
J Colloid Interface Sci. 2006 Jan 1;293(1):88-92. doi: 10.1016/j.jcis.2005.06.047. Epub 2005 Jul 27.
Nanoscaled spherical silica particles were directly coated with the titania nanoparticles by means of a heterogenic coagulation. Silica was prepared by the Stöber method, titania by a hydrolysis-condensation reaction of tetrapropylorthotitanate under acidic conditions. The on-line tracking of the coating process was performed by measuring the change in zeta potential during the gradual addition of a titania sol to the spherical silica particles. Silica particles of various sizes were used to determine the consumption of the titania sol in the dependence upon the particle size. The coated and uncoated particles were characterized by zeta-potential measurements, acoustic attenuation spectroscopy, dynamic light scattering, and scanning electron microscopy.
通过非均相凝聚法将纳米级球形二氧化硅颗粒直接用二氧化钛纳米颗粒包覆。二氧化硅采用斯托伯法制备，二氧化钛通过原钛酸四丙酯在酸性条件下的水解缩合反应制备。通过在向球形二氧化硅颗粒逐渐添加二氧化钛溶胶的过程中测量zeta电位的变化来对包覆过程进行在线跟踪。使用各种尺寸的二氧化硅颗粒来确定二氧化钛溶胶的消耗量与颗粒尺寸的关系。通过zeta电位测量、声衰减光谱、动态光散射和扫描电子显微镜对包覆和未包覆的颗粒进行表征。
