Approach to Estimation of Hamaker Constant as Taking Hofmeister Effects into Account
Approach to Estimation of Hamaker Constant as Taking Hofmeister Effects into Account
复制标题
DOI：
10.1021/acs.jpcc.7b12830
复制
发表时间：
2018-04
影响因子：
3.7
通讯作者：
Yaxue Luo;Xiaodan Gao;R. Tian;Hang Li
中科院分区：
文献类型：
--
作者：
Yaxue Luo;Xiaodan Gao;R. Tian;Hang Li
哈马克常数是描述粒子相互作用和预测胶体稳定性的一个重要材料参数。基于经典的德亚金 - 朗道 - 维韦 - 奥弗比克理论的现有方法忽略了霍夫迈斯特效应，会得出有缺陷的结果。在本文中，分别提出了考虑和不考虑霍夫迈斯特效应的哈马克常数估算方法，其中哈马克常数是通过动态光散射技术，基于临界聚沉浓度（CCC）下静电斥力和范德华引力相互作用之间的数学关系而获得的。结果表明，在Li⁺、K⁺和Cs⁺存在的情况下，蒙脱石颗粒的聚集动力学表现出显著的霍夫迈斯特效应，且CCC值显示为：Li⁺（277.2 mM）> K⁺（80.3 mM）> Cs⁺（27.2 mM）。不考虑霍夫迈斯特效应时，对于相同材料会得到完全不同的哈马克常数……
The Hamaker constant is an important material parameter for both the description of particle interaction and the prediction of colloidal stability. Existing methods based on the classic Derjaguin–Landau–Verwey–Overbeek theory ignore the Hofmeister effects and would derive flawed results. In this article, approaches to the estimation of the Hamaker constant with and without consideration of the Hofmeister effects were, respectively, suggested, where the Hamaker constant was obtained on the basis of the mathematic relationship between electrostatic repulsive and van der Waals attractive interaction at the critical coagulation concentration (CCC) by using the dynamic light scattering technique. It indicated that the montmorillonite particles aggregation kinetics in the presence of Li+, K+, and Cs+ exhibited remarkable Hofmeister effects and the CCC values show: Li+ (277.2 mM) > K+ (80.3 mM) > Cs+ (27.2 mM). Without consideration of Hofmeister effects, completely distinct Hamaker constants for the same materi...