Core−Shell-Structured Magnetic Ternary Nanocubes

Abstract

We report a novel core−shell-structured ternary nanocube of MnZn ferrite synthesized by controlling the reaction temperature and composition in the absence of conventionally used reducing agents. The highly monodispersed core−shell structure consists of an Fe₃O₄ core and an MnZn Ferrite shell. The observation of a Moiré pattern indicates that the core and the shell are two highly crystalline materials with slightly different lattice constants that are rotated relative to each other by a small angle. The ternary core−shell nanocubes display magnetic properties regulated by a combination of the core−shell composition and exhibit an increased coercivity and field-cooled/zero-field-cooled characteristics drastically different from those of regular MnZn ferrite nanoparticles. The ability to engineer the spatial nanostructures of ternary magnetic nanoparticles in terms of shape and composition offers atomic-level versatility in fine-tuning the nanoscale magnetic properties.