TY - JOUR

T1 - On the adsorption properties of magnetic fluids

T2 - Impact of bulk structure

AU - Kubovcikova, Martina

AU - Gapon, Igor V.

AU - Zavisova, Vlasta

AU - Koneracka, Martina

AU - Petrenko, Viktor I.

AU - Soltwedel, Оlaf

AU - Almasy, László

AU - Avdeev, Mikhail V.

AU - Kopcansky, Peter

PY - 2017/4/1

Y1 - 2017/4/1

N2 - Adsorption of nanoparticles from magnetic fluids (MFs) on solid surface (crystalline silicon) was studied by neutron reflectometry (NR) and related to the bulk structural organization of MFs concluded from small-angle neutron scattering (SANS). The initial aqueous MF with nanomagnetite (co-precipitation reaction) stabilized by sodium oleate and MF modified by a biocompatible polymer, poly(ethylene glycol) (PEG), were considered. Regarding the bulk structure it was confirmed in the SANS experiment that comparatively small and compact (size~30 nm) aggregates of nanoparticle in the initial sample transfer to large and developed (size>130 nm, fractal dimension 2.7) associates in the PEG modified MF. This reorganization in the aggregates correlates with the changes in the neutron reflectivity that showed that a single adsorption layer of individual nanoparticles on the oxidized silicon surface for the initial MF disappears after the PEG modification. It is concluded that all particles in the modified fluid are in the aggregates that are not adsorbed by silicon.

AB - Adsorption of nanoparticles from magnetic fluids (MFs) on solid surface (crystalline silicon) was studied by neutron reflectometry (NR) and related to the bulk structural organization of MFs concluded from small-angle neutron scattering (SANS). The initial aqueous MF with nanomagnetite (co-precipitation reaction) stabilized by sodium oleate and MF modified by a biocompatible polymer, poly(ethylene glycol) (PEG), were considered. Regarding the bulk structure it was confirmed in the SANS experiment that comparatively small and compact (size~30 nm) aggregates of nanoparticle in the initial sample transfer to large and developed (size>130 nm, fractal dimension 2.7) associates in the PEG modified MF. This reorganization in the aggregates correlates with the changes in the neutron reflectivity that showed that a single adsorption layer of individual nanoparticles on the oxidized silicon surface for the initial MF disappears after the PEG modification. It is concluded that all particles in the modified fluid are in the aggregates that are not adsorbed by silicon.

KW - Adsorption of magnetic nanoparticles

KW - Effect of gravity

KW - Ferrofluid structure

KW - Ferrofluids

KW - Magnetic fluids

KW - Neutron reflectometry

KW - Small-angle neutron scattering

UR - http://www.scopus.com/inward/record.url?scp=85006070807&partnerID=8YFLogxK

U2 - 10.1016/j.jmmm.2016.10.104

DO - 10.1016/j.jmmm.2016.10.104

M3 - Article

AN - SCOPUS:85006070807

VL - 427

SP - 67

EP - 70

JO - Journal of Magnetism and Magnetic Materials

JF - Journal of Magnetism and Magnetic Materials

SN - 0304-8853

ER -