论文标题
异丙醇溶液中1：1电解质中的二氧化硅颗粒之间的力
Forces between Silica Particles in Isopropanol Solutions of 1:1 Electrolytes
论文作者
论文摘要
二氧化硅表面之间的异丙醇溶液之间的相互作用是用基于原子力显微镜的胶体探针技术测量的。特别是，研究了1：1电解质对二氧化硅颗粒之间相互作用的影响。在这些系统中发现了很多不同的力。也就是说，观察到范德华，双层，有吸引力的非DLVO，排斥性溶剂化和阻尼的振荡相互作用。双层排斥的测得的衰减长度大大大于根据名义盐浓度计算出的Debye长度。这些偏差是由酒精溶液中明显的离子配对引起的。在低于10 nm的分离时，观察到了其他有吸引力和排斥性的非DLVO力。前者可能是由强烈的离子吸附引起的电荷异质性引起的，而后者源自靠近表面的异丙醇分子的结构。最后，在浓度升高时，发现了从单调到阻尼振荡相互作用的过渡。
Interactions between silica surfaces across isopropanol solutions are measured with colloidal probe technique based on atomic force microscope. In particular, the influence of 1:1 electrolytes on the interactions between silica particles is investigated. A plethora of different forces are found in these systems. Namely, van der Waals, double-layer, attractive non-DLVO, repulsive solvation, and damped oscillatory interactions are observed. The measured decay length of the double-layer repulsion is substantially larger than Debye lengths calculated from nominal salt concentrations. These deviations are caused by pronounced ion pairing in alcohol solutions. At separation below 10 nm, additional attractive and repulsive non-DLVO forces are observed. The former are possibly caused by charge heterogeneities induced by strong ion adsorption, whereas the latter originate from structuring of isopropanol molecules close to the surface. Finally, at increased concentrations the transition from monotonic to damped oscillatory interactions is uncovered.
