Anisotropy Induced Tunable Magnetic Properties of Chemically Synthesized Copper Ferrite (CuxFe1-xO4) Nanoparticles with Different Composition

Abstract

Here we report the structural and magnetic properties of cluster of ultrafine copper ferrite (Cu_xFe_1-xO₄) nanoparticles with different Cu:Fe composition synthesized by aqueous chemical reduction technique. The morphological, microstructural and compositional studies confirm the formation of Cu_xFe_1-xO₄ nanoparticles with varied Cu and Fe percentages which are polycrystalline in nature with fcc structure and average size of ~20 nm. Thermal stability and chemically purity of ferrite nanoparticles are ensured by analyzing the TGA/DTA curve in the temperature range 30-1000 ^oC. Magnetization vs magnetic field (M-H) hysteresis loops measured at two different temperatures (80K and 300K) reveal the typical ferromagnetic behavior of Cu_xFe_1-xO₄ nanoparticles with a systematic change in the saturation magnetization (M_S), coercive field (H_c), remanent magnetization (M_r), Squareness (M_r/M_S), hardness (α) and effective anisotropy energy constant (K_eff) with the variation of Cu and Fe percentages. Tunable magnetic properties of ferrite nanoparticles with the variation of magnetic Fe and non-magnetic Cu are attributed to the modulation of effective anisotropy originated from the surface spin randomization.