Thermal annealing induced enhancement of room temperature magnetic memory effect in Fe-doped NiO nanoparticles

We report room temperature (RT) ferromagnetism and magnetic memory effect in Ni0.95Fe0.05O nanoparticles (NPs) synthesize by hydrothermal method followed by post-annealing in an ambient atmosphere. The temperature and time-dependent magnetization measurements show that the effect of post-annealing at higher temperatures leads to enhancement in the intraparticle interactions. The enhanced intraparticle interaction has provided additional magnetic anisotropy energy resulting in RT ferromagnetic (FM) properties and enhanced magnetic memory effect. The findings from this study will be useful for the development and understanding of RT FM materials to facilitate the integration of spintronic devices.