Thermodiffusion of charged micelles.
We study diffusion of charged nanoparticles in a temperature gradient and derive the corresponding Ludwig-Soret transport coefficient. Charge effects are found to enhance thermodiffusion by up to 2 orders of magnitude. We show that the inverse Soret coefficient 1/S(T) is a linear function of the colloid density n; the proportionality factor, or second virial coefficient, varies algebraically with inverse salinity, n0(-alpha); the precise value of the exponent alpha depends on the ratio of particle size and Debye length. Our findings compare favorably with experimental observations and provide, without adjustable parameters, a good fit to the data on 3-nm sodium dodecylsulfate micelles.
Fayolle
Sébastien
S
CPMOH, CNRS-Université Bordeaux 1, 351 cours de la Libération, 33405 Talence, France.
Bickel
Thomas
T
Le Boiteux
Sylvie
S
Würger
Alois
A