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Title: Charging mechanism in colloidal particles leading to a linear relation between charge and size

Abstract

Colloidal particles that are dissolved in a liquid can become charged by preferential adsorption or dissociation of surface molecules. The assumption of a constant surface charge density leads to a particle charge that is proportional to the square of the radius. Recent experiments however have shown that in a number of cases the charge is linearly proportional to its size. We present a simple model for the charging of colloidal particles leading to a linear relation between charge and size in the framework of the mean-field Poisson-Boltzmann theory. The model is based on preferential adsorption or dissociation of surface molecules, in combination with a large concentration of chargeable surface sites. The model also predicts a surface potential that is independent of the particle size. Numerical simulations show that this model is in good agreement with analytical approximations.

Authors:
; ; ;  [1]
  1. Ghent University, Electronics and Information Systems, Sint-Pietersnieuwstraat 41, Ghent B-9000 (Belgium)
Publication Date:
OSTI Identifier:
21072395
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevE.75.031405; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ADSORPTION; APPROXIMATIONS; BOLTZMANN EQUATION; CHARGE DENSITY; COLLOIDS; COMPUTERIZED SIMULATION; DISSOCIATION; LIQUIDS; MEAN-FIELD THEORY; MOLECULES; PARTICLE SIZE; PARTICLES; POISSON EQUATION; SURFACE POTENTIAL; SURFACES

Citation Formats

Strubbe, Filip, Beunis, Filip, Marescaux, Matthias, and Neyts, Kristiaan. Charging mechanism in colloidal particles leading to a linear relation between charge and size. United States: N. p., 2007. Web. doi:10.1103/PHYSREVE.75.031405.
Strubbe, Filip, Beunis, Filip, Marescaux, Matthias, & Neyts, Kristiaan. Charging mechanism in colloidal particles leading to a linear relation between charge and size. United States. doi:10.1103/PHYSREVE.75.031405.
Strubbe, Filip, Beunis, Filip, Marescaux, Matthias, and Neyts, Kristiaan. Thu . "Charging mechanism in colloidal particles leading to a linear relation between charge and size". United States. doi:10.1103/PHYSREVE.75.031405.
@article{osti_21072395,
title = {Charging mechanism in colloidal particles leading to a linear relation between charge and size},
author = {Strubbe, Filip and Beunis, Filip and Marescaux, Matthias and Neyts, Kristiaan},
abstractNote = {Colloidal particles that are dissolved in a liquid can become charged by preferential adsorption or dissociation of surface molecules. The assumption of a constant surface charge density leads to a particle charge that is proportional to the square of the radius. Recent experiments however have shown that in a number of cases the charge is linearly proportional to its size. We present a simple model for the charging of colloidal particles leading to a linear relation between charge and size in the framework of the mean-field Poisson-Boltzmann theory. The model is based on preferential adsorption or dissociation of surface molecules, in combination with a large concentration of chargeable surface sites. The model also predicts a surface potential that is independent of the particle size. Numerical simulations show that this model is in good agreement with analytical approximations.},
doi = {10.1103/PHYSREVE.75.031405},
journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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