Magnetic characterization of vermiculite-based magnetic nanocomposites

This study reports on the temperature dependence of hysteresis loops of magnetic nanocomposites consisting of iron oxide-based nanoparticles supported within exfoliated vermiculate. Two magnetic nanocomposite samples (IMFV and SMFV) were prepared by treating the exfoliated vermiculite with two magnetic fluid samples; an ionic magnetic fluid (IMF) and a surfacted magnetic fluid (SMF). X-ray diffraction and transmission electron microscopy of the magnetic phase powders provided the average diameter and diameter dispersity of the nanosized magnetic particles. The saturation magnetization, supported by the average nanoparticle size obtained from X-ray diffraction measurements, indicates the size-selectivity of the encapsulated nanoparticles by the hosting template. This finding is extremely interesting as it indicates the use of exfoliated vermiculite as a size-sort template for nanosized particles suspended as a colloid.