Related Experiment Video
Updated: Jul 17, 2026

Fine-tuning the Size and Minimizing the Noise of Solid-state Nanopores
Published on: October 31, 2013
Van der waals-like isotherms in a confined electrolyte by spherical and cylindrical nanopores
Gabriel E Aguilar-Pineda1, Felipe Jiménez-Angeles, Jiang Yu
1Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa Apartado Postal 55-534, 09340 México, D. F., México.
Abstract:
Electrolytes confined by spherical, cylindrical, and slit-like charged nanopores are studied. Results for ionic distribution profiles, pressures of the confined fluid, and absorption isotherms are obtained through the hypernetted chain/mean spherical approximation (HNC/MSA) integral equations theory. In spherical and cylindrical geometries, an inward, non-monotonic behavior of the pressure is found as confinement increases, implying a negative compressibility. The pressure vs volume isotherms resemble liquid-vapor van der Waals-like phase transition diagrams. This effect is correlated with a charge separation inside a spherical pore previously reported (Phys. Rev. Lett., 79, 3656, 1997). Here, the mechanism of charge separation and negative compressibility are explored in detail. When compared with the slit-like pore pressure, important qualitative differences are found.
Related Concept Videos
Debye–Huckel–Onsager Conductance Equation
Pore Transport and Ion-Pair Transport
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct microscopic...
Dialysis
Electrolytes: van't Hoff Factor
Theory of Strong Electrolytes
Aquaporins

