Structural Studies of Ferrofluids by Small-Angle Neutron Scattering

Abstract. The aim of this paper is to present method to investigate the properties of magnetic fluids by means of small angle neutron scattering. Ferrofluids are dispersions of small, single-domain magnetic particles suspended in a fluid carrier. The neutron scattering methods have been largely used the last two decades for the determination of structural properties of magnetic liquids at microscopic level. There can be investigated the structure of the particle, the aggregation phenomena, the magnetic liquid dynamics, particle-surfactant interaction, surfactant liquid-base interaction and structure, magnetic behavior of the samples. Experiments on small angle neutron scattering were carried out on SANS instrument YuMO in function at IBR-2 high-pulsed reactor at the Fran

Preparation and Properties of ε-Fe3N-Based Magnetic Fluid

In this work, ε-Fe3N nanoparticles and ε-Fe3N-based magnetic fluid were synthesized by chemical reaction of iron carbonyl and ammonia gas. The size of ε-Fe3N nanoparticles was tested by TEM and XRD. Stable ε-Fe3N-based magnetic fluid was prepared by controlling the proper ratio of carrier liquid and surfactant. The saturation magnetization of stable ε-Fe3N-based magnetic fluid was calculated according to the volume fraction of the particles in the fluid. The result shows that both the calculated and measured magnetizations increase by increasing the particle concentration. With the increasing concentration of the ε-Fe3N particles, the measured value of the magnetic fluid magnetization gradually departs from the calculated magnetization, which was caused by agglomeration affects due to large volume fraction and large particle size

Neutron Investigations of Ferrofluids

A review of neutron scattering researches of various magnetic fluids (ferrofluids) is made. Advantages and disadvantages of other complementary methods for the structure characterization of ferrofluids are discussed. The small-angle neutron scattering (SANS) method with a wavelength of 0.1–1 nm is a classic example of applying radiation to the determination of a structure in liquid nanosystems on a scale of 1–100 nm. The capabilities of the SANS method for the analysis of a magnetic fluid structure are illustrated by real examples