Thermal and Magnetic Properties of Nanostructured Ferrimagnetic Composites with Graphene - Graphite Fillers

TL;DR

This study demonstrates that adding graphene and graphite fillers to ferrimagnetic composites significantly enhances thermal conductivity while maintaining magnetic properties, with potential applications in energy and electronics.

Contribution

It provides experimental evidence that graphene-graphite fillers improve thermal conductivity in ferrimagnetic composites without degrading magnetic properties.

Findings

Thermal conductivity increased by 2.6 times with 5 wt.% filler addition.

Graphene and graphite preserved their structure during processing.

Enhanced heat conduction due to phonon properties of fillers.

Abstract

We report the results of an experimental study of thermal and magnetic properties of nanostructured ferrimagnetic iron oxide composites with graphene and graphite fillers synthesized via the current activated pressure assisted densification. The thermal conductivity was measured using the laser-flash and transient plane source techniques. It was demonstrated that addition of 5 wt. % of equal mixture of graphene and graphite flakes to the composite results in a factor of x2.6 enhancement of the thermal conductivity without significant degradation of the saturation magnetization. The microscopy and spectroscopic characterization reveal that sp2 carbon fillers preserve their crystal structure and morphology during the composite processing. The strong increase in the thermal conductivity was attributed to the excellent phonon heat conduction properties of graphene and graphite. The results are important for energy and electronic applications of the nanostructured permanent magnets.