Analysis of Novel Superparamagnetic Nanoparticles for Achieving Better Self-Healing Insulating Materials

Self-healing insulating polymers based on magnetic melting interdiffusion have put forward higher requirements on the heating power of superparamagnetic nanoparticles. We designed magnetic nanoparticles of various compositions by utilizing metal dopant substitution and exchange coupling effect. Thermal decomposition of organic precursors was used to prepare the nanoparticles. Crystallographic, chemical, and magnetic characterization methods were used to verify the effectiveness of our design and synthesis. Single crystallinity was found for nanoparticles with both single component and core-shell structures. Chemical composition analysis was conducted to demonstrate the coreshell structure and to reveal the difference between nominal and actual chemical formulae. Measurements on magnetic hysteresis loops and heating powers have suggested a higher heating efficiency of core-shell nanoparticles than maghemite which was used in conventional self-healing strategies.