Electric double layer and orientational ordering of water dipoles in narrow channels within a modified Langevin Poisson-Boltzmann model
ID Drab, Mitja (Author), ID Gongadze, Ekaterina (Author), ID Kralj-Iglič, Veronika (Author), ID Iglič, Aleš (Author)

.pdfPDF - Presentation file, Download (2,62 MB)
MD5: 725A562708C6EC95522CB7076F299FFC
URLURL - Source URL, Visit https://www.mdpi.com/1099-4300/22/9/1054 This link opens in a new window

The electric double layer (EDL) is an important phenomenon that arises in systems where a charged surface comes into contact with an electrolyte solution. In this work we describe the generalization of classic Poisson-Boltzmann (PB) theory for point-like ions by taking into account orientational ordering of water molecules. The modified Langevin Poisson-Boltzmann (LPB) model of EDL is derived by minimizing the corresponding Helmholtz free energy functional, which includes also orientational entropy contribution of water dipoles. The formation of EDL is important in many artificial and biological systems bound by a cylindrical geometry. We therefore numerically solve the modified LPB equation in cylindrical coordinates, determining the spatial dependencies of electric potential, relative permittivity and average orientations of water dipoles within charged tubes of different radii. Results show that for tubes of a large radius, macroscopic (net) volume charge density of coions and counterions is zero at the geometrical axis. This is attributed to effective electrolyte charge screening in the vicinity of the inner charged surface of the tube. For tubes of small radii, the screening region extends into the whole inner space of the tube, leading to non-zero net volume charge density and non-zero orientational ordering of water dipoles near the axis.

Keywords:electric double layer, orientational ordering of water dipoles, Helmholtz free energy, modified Langevin Poisson-Boltzmann model
Work type:Article
Typology:1.01 - Original Scientific Article
Organization:FE - Faculty of Electrical Engineering
ZF - Faculty of Health Sciences
Publication status:Published
Publication version:Version of Record
Number of pages:19 str.
Numbering:Vol. 22, iss. 9, art. 1054
PID:20.500.12556/RUL-134268 This link opens in a new window
ISSN on article:1099-4300
DOI:10.3390/e22091054 This link opens in a new window
COBISS.SI-ID:30268931 This link opens in a new window
Publication date in RUL:04.01.2022
Copy citation
Share:Bookmark and Share

Record is a part of a journal

Shortened title:Entropy
COBISS.SI-ID:515806233 This link opens in a new window


License:CC BY 4.0, Creative Commons Attribution 4.0 International
Description:This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
Licensing start date:21.09.2020

Secondary language

Keywords:električni dvojni sloj, orientacijsko urejanje vodnih dipolov, Helmholtzeva prosta energija, evolucijski modificiran Langevin Poisson-Boltzmannov model


Funder:ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
Project number:P2-0232
Name:Funkcije in tehnologije kompleksnih sistemov

Funder:ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
Project number:P3-0388
Name:Mehanizmi varovanja zdravja

Funder:ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
Project number:J3-9262
Name:Napredne tehnologije obdelave individualiziranih 3D tiskanih implantatov za preprečevanje bakterijskih okužb

Funder:ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
Project number:J1-9162
Name:Neurotoksičnost ali neuroprotektivnost nanomaterialov: vpliv biokorone

Similar documents

Similar works from RUL:
Similar works from other Slovenian collections: