1. Density functional theory study on ion adsorption and electroosmotic flow in a membrane with charged cylindrical pores
- Author
-
Yuan-Xiang Zheng, Yan Xin, and Yang-Xin Yu
- Subjects
Valence (chemistry) ,Chemistry ,Monte Carlo method ,Biophysics ,Analytical chemistry ,02 engineering and technology ,Electrolyte ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Ion ,Adsorption ,Chemical physics ,Electric field ,Density functional theory ,Surface charge ,Physical and Theoretical Chemistry ,0210 nano-technology ,Molecular Biology - Abstract
Ion adsorption and electroosmotic flow induced by an external electric field have a variety of practical applications, especially for membrane technology. In this work, a partially perturbative density functional theory (DFT) based on the modified fundamental measure theory was applied to investigate the ion density distributions and partitions in a charged cylindrical pore. Different types of electrolyte solutions, including both charge symmetric and asymmetric, were examined using the proposed theory with various pore diameters, bulk densities, ion valencies and surface charge densities. The ion concentration profiles calculated with the theory exhibit good agreements with the results of the Monte Carlo simulations, while the results of the Poisson–Boltzmann equation deviate greatly especially for the high valence electrolytes in narrow cylindrical pores. Some interesting phenomena discovered in both experiments and simulations, such as the reverse distribution of the ions and charge inversion, ...
- Published
- 2015