Chakraborty Suman, Padhy Sourav
Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur-721302, India.
ACS Nano. 2008 Oct 28;2(10):2029-36. doi: 10.1021/nn800343h.
The electrical conductivity of colloidal suspensions containing nanoscale conducting particles is nontrivially related to the particle volume fraction and the electrical double layer thickness. Classical electrochemical models, however, tend to grossly overpredict the pertinent effective electrical conductivity values, as compared to those obtained under experimental conditions. We attempt to address this discrepancy by appealing to the complex interconnection between the aggregation kinetics of the nanoscale particles and the electrodynamics within the double layer. In particular, we model the consequent alterations in the effective electrophoretic mobility values of the suspension by addressing the fundamentals of agglomeration-deagglomeration mechanisms through the pertinent variations in the effective particulate dimensions, solid fractions, as well as the equivalent suspension viscosity. The consequent alterations in the electrical conductivity values provide a substantially improved prediction of the corresponding experimental findings and explain the apparent anomalous behavior predicted by the classical theoretical postulates.
含有纳米级导电颗粒的胶体悬浮液的电导率与颗粒体积分数和电双层厚度有着复杂的关系。然而，与实验条件下获得的值相比，经典电化学模型往往会严重高估相关的有效电导率值。我们试图通过探讨纳米级颗粒的聚集动力学与双层内电动力学之间的复杂相互联系来解决这一差异。特别是，我们通过有效颗粒尺寸、固体分数以及等效悬浮液粘度的相关变化，研究团聚 - 解聚机制的基本原理，从而对悬浮液有效电泳迁移率值的相应变化进行建模。电导率值的相应变化对相应的实验结果提供了显著改进的预测，并解释了经典理论假设所预测的明显异常行为。
