Size-dependent magnetic properties of Mn-Co-NiO based heterostructured nanoparticles

In this work, we investigate the synthesis, along with structural and magnetic properties, of novel Mn-Co-NiO-based heterostructured nanocrystals (HNCs). The objective is to develop novel, well-structurally ordered inverted antiferromagnetic (AFM) NiO–ferrimagnetic (FiM) spinel phase overgrowth HNCs. Inverted HNCs are particularly promising for device applications because their properties more easily controlled by having well-ordered AFM cores, which can result in structures large coercivities, tunable blocking temperatures, other enhanced effects. synthesis accomplished using a two-step process: first step, NiO nanoparticles synthesized thermal decomposition method. Subsequently, Mn-Co phases grown on via hydrothermal nanophase epitaxy, fixed pH level (∼5.3) aqueous medium. This was selected based previous work our laboratory showing that NiO/Mn 3 O 4 constant size have optimal coercivity exchange bias when at 5.0. crystalline structure gross morphology been analyzed X-ray diffraction (XRD) Scanning Electron Microscopy (SEM) techniques, respectively. Analysis these techniques shows composed core CoMn 2 phase. Rietveld refinement XRD data has rocksalt (Fm[Formula: see text]m) cubic crystal ( I4 1 / amd) structure. Moreover, an increased relative amount deposited decreasing particle during results from PPMS magnetization high-resolution transmission electron microscopy (HRTEM) characterization discussed herein.