Two-stage kinetics of field-induced aggregation of medium-sized magnetic nanoparticles

H. Ezzaier (1, 2) , J. Alves Marins (1) , I. Razvin (1) , Micheline Abbas (3) , A. Ben Haj Amara (2) , A. Zubarev (4) , P. Kuzhir (1)

1 INPHYNI - Institut de Physique de Nice
2 PMLNMH - Laboratoire de Physique des Matériaux Lamellaires et Nano Matériaux Hybrides
3 LGC - Laboratoire de Génie Chimique
4 UrFU - Ural Federal University [Ekaterinburg]

The present paper is focused on theoretical and experimental study of the kinetics of field-induced aggregation of magnetic nanoparticles of a size range of 20-100 nm. Our results demonstrate that (a) in polydisperse suspensions, the largest particles could play a role of the centers of nucleation for smaller particles during the earliest heterogeneous nucleation stage; (b) an intermediate stage of the aggregate growth (due to diffusion and migration of individual nanoparticles towards the aggregates) is weakly influenced by the magnetic field strength; (c) the stage of direct coalescence of drop-like aggregates (occurring under magnetic attraction between them) plays a dominant role at the intermediate and late stages of the phase separation, with the timescale decreasing as a square of the aggregate magnetization.

Domaines: Matière Molle [cond-mat.soft]

H. Ezzaier, J. Alves Marins, I. Razvin, Micheline Abbas, A. Ben Haj Amara, et al.. Two-stage kinetics of field-induced aggregation of medium-sized magnetic nanoparticles. Journal of Chemical Physics, 2017, 146 (11), ⟨10.1063/1.4977993⟩. ⟨hal-01672513⟩