Interfacial forces between silica surfaces measured by atomic force microscopy
Interfacial forces between silica surfaces measured by atomic force microscopy作者机构:Key Laboratory of Northwest Water Resource Environment and Ecology MOE Xi'an University of Architecture and Technology Xi'an 710055 China
出 版 物:《Journal of Environmental Sciences》 (环境科学学报(英文版))
年 卷 期:2009年第21卷第1期
页 面:30-34页
核心收录:
学科分类:0830[工学-环境科学与工程(可授工学、理学、农学学位)] 08[工学] 0803[工学-光学工程]
主 题:colloid probe DLVO theory solvation forces interfacial interactions
摘 要:Colloidal particle stability and some other interfacial phenomena are governed by interfacial force interactions. The two well known forces are van der Waals force and electrostatic force, as documented by the classical Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory. Moreover, advances in modern instrumentation and colloid science suggested that some short-ranged forces or structure forces are important for relevant colloidal systems. The interfacial and/or molecular forces can be measured as a resultant force as function of separation distance by atomic force microscopy (AFM) colloid probe. This article presents a discussion on AFM colloid probe measurement of silica particle and silica wafer surfaces in solutions with some technical notifications in measurement and data convolution mechanisms. The measured forces are then analyzed and discussed based on the 'constant charge' and 'constant potential' models of DLVO theory. The difference between the prediction of DLVO theory and the measured results indicates that there is a strong short-range structure force between the two hydrophilic surfaces, even at extremely low ionic concentration, such as Milli-Q water purity solution.