新的实验方法正确考虑停滞和扩散层导电性在泽塔电位的确定
Matthias Frangenberg1,2, Annette M Schmidt2, Jan Wilkens1
1Faculty of Applied Natural Sciences, TH Köln - University of Applied Sciences, Leverkusen D-51379, Germany.
Langmuir : the ACS journal of surfaces and colloids
|February 19, 2025
概括
准确的泽塔电位测定需要考虑表面导电性. 这项研究引入了一种新方法,将导电性测量与电声学和电泳学技术相结合,使用杜金数来提高可靠性.
科学领域:
- 合体和接口科学科学
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
背景情况:
- 在状分散中确定泽塔电位对于理解稳定性和行为至关重要.
- 放松效应受到电气双层极化和表面导电性的影响,通常会使精确的泽塔电位测量变得复杂.
- 现有的方法可能不能完全考虑表面导电性,导致不一致.
研究的目的:
- 开发和验证一种新的方法,用于在聚合物分散中准确地确定泽塔电位.
- 将导电性测量与电声学和电泳学技术相结合.
- 研究表面导电性对放松效应的贡献及其对泽塔电位值的影响.
主要方法:
- 结合导电性测量 (分散和介质) 与电声学 (杂合振动电流 - CVI) 和电光学 (电光学光散射 - ELS) 泽塔电位的确定.
- 使用Maxwell-Wagner-O'Konski理论分析导电数据以获得杜金数.
- 应用了先进的CVI理论和ELS理论 (杜金-塞米尼金,修改的Ohshima,Healy和White),考虑实验确定的杜金数.
主要成果:
- 杜金数被实验确定为各种聚合物分散,揭示了显著的表面导电性.
- 发现扩散层和停滞层都对表面导电性做出了重大贡献.
- 先进的CVI理论得到了验证,因为它对广泛的粒子体积分数的表面导电性进行了准确的考虑.
- 通过CVI和ELS方法获得的Zeta潜力值,包含杜金数,显示出很好的一致性.
结论:
- 杜金数是可靠连接导电性,电泳性和电声学测量的关键参数.
- 准确的泽塔电位测定需要考虑扩散层和停滞层的表面导电性贡献.
- 拟议的综合方法为表征体分散提供了可靠的方法,特别是在高度下.
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