Surface tension of electrolyte interfaces: Ionic specificity within a field-theory approach
Surface tension of electrolyte interfaces: Ionic specificity within a field-theory approach
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DOI：
10.1063/1.4905954
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发表时间：
2015-01-28
影响因子：
4.4
通讯作者：
Podgornik, Rudi
中科院分区：
文献类型：
--
作者：
Markovich, Tomer;Andelman, David;Podgornik, Rudi
我们研究了在空气/水和油/水界面的离子溶液的表面张力，通过使用场论方法，包括一个有限的近端表面区域与离子特定的相互作用。自由能扩展到一阶环展开超出平均场的结果。我们计算了过量的表面张力，并获得分析预测，团聚Onsager-Samaras开拓性的结果（这与实验数据不一致），与离子特异性的霍夫迈斯特系列。我们推导出解析的表面张力依赖于离子强度，离子大小，和离子表面相互作用，并因此表明，Onsager-Samaras的结果是一致的，超过平均场的结果与单回路校正。我们的理论很好地适应了广泛的盐浓度为不同的单价离子使用一个适合的参数，每个电解质和再现反霍夫迈斯特系列的阴离子在空气/水和油/水界面。(C)2015 AIP Publishing LLC.
We study the surface tension of ionic solutions at air/water and oil/water interfaces by using field-theoretical methods and including a finite proximal surface-region with ionic-specific interactions. The free energy is expanded to first-order in a loop expansion beyond the mean-field result. We calculate the excess surface tension and obtain analytical predictions that reunite the Onsager-Samaras pioneering result (which does not agree with experimental data), with the ionic specificity of the Hofmeister series. We derive analytically the surface-tension dependence on the ionic strength, ionic size, and ion-surface interaction, and show consequently that the Onsager-Samaras result is consistent with the one-loop correction beyond the mean-field result. Our theory fits well a wide range of salt concentrations for different monovalent ions using one fit parameter per electrolyte and reproduces the reverse Hofmeister series for anions at the air/water and oil/water interfaces. (C) 2015 AIP Publishing LLC.