Enhancement of ferromagnetic properties in (Fe, Ni) co-doped ZnO flowers by pulsed magnetic field processing

Abstract

In this study, Zn0.97Fe0.01Ni0.02O diluted magnetic semiconductor (DMS) flowers were fabricated through hydrothermal method with 4T (Tesla) pulsed magnetic field (PMF). Rietveld refinement of X-ray diffraction (XRD) patterns and Raman analysis indicated that the synthesized samples have the hexagonal wurtzite structure without any other secondary (impurity) phases. The O1s X-ray photoelectron spectroscopy (XPS) and Raman measurements of the synthesized samples showed the existence of oxygen vacancy (VO). The results indicated that PMF could increase the contents of VO and doped ions. The magnetic measurement showed that the room temperature ferromagnetic (RTFM) property of (Fe, Ni) co-doped ZnO is enhanced by PMF. The enhancement of RTFM is attributed to the intrinsic interaction of magnetic ions (Fe3+, Ni2+) via VO created by pulsed magnetic field processing.