Ionic magnetic fluids inpolar solvents with tuned counter-ions

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:431

Article; Proceedings Paper

Lopes Filomeno, C.^1,2  Kouyate, M.¹  Cousin, E.³  Demouchy, G.^1,4  Dubois, E.¹  Michot, L.¹  Meriguet, G.¹  Perzynski, R.¹  Peyre, V.¹  Sirieix-Plenet, J.¹  Tourinho, F. A.² 

[1] UPMC Univ Paris 06, Sorbonne Univ, CNRS, Lab PHENIX, Paris, France

[2] Univ Brasilia, Inst Quim, Grp Fluidos Complexos, Brasilia, DF, Brazil

[3] CE Saclay, Lab Leon Brillouin, Gif Sur Yvette, France

[4] Univ Cergy Pontoise, Dept Phys, Cergy Pontoise, France

关键词: Ionic colloidal dispersion;    Dimethylsulfoxide;    Ethylammonium nitrate;    Ludwig-Soret coefficient;    Seebeck coefficient;   

DOI  :  10.1016/j.jmmm.2016.07.050

来源: Elsevier

【 摘 要 】

The aim of the present study is to propose a new reproducible method for preparing colloidal dispersions of electrostatically charged nanoparticles (NPs) in polar solvents with different kinds of counter-ions. Maghemite NPs are here dispersed in solvents of different dielectric constant, namely water, dimethylsulfoxide (DMSO) and an ionic liquid, ethylammonium nitrate (EAN). If the existence of a NP superficial charge happens to be necessary for the colloidal stability of the dispersions in these three solvents, the standard DLVO theory cannot be used any more to describe the colloidal stability in EAN. The structure of the dispersions and the strength of the interparticle repulsion are investigated by small angle X-ray scattering measurements, in association with LudwigSoret coefficient determinations. Specificities, associated to the nature of the counter-ions are identified in this work on the colloidal stability, on the interparticle repulsion and on the LudwigSoret coefficient. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

Free