Room temperature ferromagnetism and structural characterization of Fe,Ni co-doped ZnO nanocrystals

A systematic investigation on the structural and magnetic properties of FexNi0.01Zn1−xO (x = 0.01, 0.03, 0.05) nanoparticles synthesized by easy and inexpensive solution combustion technique is presented. X-ray diffraction (XRD), HRTEM and selected area electron diffraction (SAED) results show single phase nature with hexagonal wurtzite structure, and reveal the incorporation of Fe and Ni ions into lattice positions of Zn ions in ZnO lattice. Micro-Raman analysis suggests the suppression of surface defects with increasing Fe content. The magnetization measurements results into ferromagnetic state for all co-doped samples. Saturation magnetization increases with Fe doping indicating the role of interaction between Fe and Ni ions. Ferromagnetic interaction enhances at low temperature and remains non-zero above room temperature as suggested by magnetization vs. temperature measurements.