Thermocharge of a hot spot in an electrolyte solution

Arghya Majee (1, 2) , Alois Würger (3)

1 Max-Planck-Institut für Intelligente Systeme
2 Institut für Theoretische Physik IV
3 LOMA - Laboratoire Ondes et Matière d'Aquitaine

We discuss the thermoelectric properties of a locally heated micron-size volume in an electrolyte solution. We find that such a hot spot carries a net charge Q which, for an excess temperature of 10 K, may attain hundreds of elementary charges. The corresponding Seebeck electric field E increases linearly with the radius r inside the heated area, then goes through a maximum, and decays as 1/r2 at larger distances. Our results could be relevant to optothermal actuation of electrolytes and colloidal suspensions.

Domaines: Matière Molle [cond-mat.soft]

Arghya Majee, Alois Würger. Thermocharge of a hot spot in an electrolyte solution. Soft Matter, 2013, 9 (7), pp.2145-2153. ⟨10.1039/C2SM26680F⟩. ⟨hal-00780465⟩