Room temperature ferromagnetic behavior in the nanocrystals of Fe doped ZnO synthesized by soft chemical route

Abstract

In the present study, nanocrystalline undoped and Fe (5 wt.%) doped ZnO powder has been synthesized by soft chemical route. The structural, nano/microstructural, vibrational and magnetic properties of these samples have been studied as a function of calcination temperature (400°C to 1100°C). X-ray diffraction analysis of Fe doped ZnO powder has shown the major nanocrystalline wurtzite (ZnO) phase and the minor cubic spinel-like secondary nanocrystalline phase at 700°C. At calcination temperature of 700°C, the magnetization and coercivity have been enhanced in Fe doped ZnO. As the calcination temperature increased to 1100°C, the major phase of ZnO and minor cubic spinel-like secondary phase turned into bulk in doped ZnO. Interestingly, the reduced magnetization and zero coercivity have been observed in this case. These changes are attributed to the conversion of secondary nanocrystalline ferromagnetic spinel phase to its bulk paramagnetic phase. The degree of inversion i.e. the occupancy of both sites with different symmetry by ferric ions is proposed to be solely responsible for the unusual behavior. Keywords: ZnO nanocrystal; Fe doped ZnO nanocrystal; sol-gel route; X-ray diffraction; secondary phase; room temperature ferromagnetism Room temperature ferromagnetic behavior in the nanocrystals of Fe doped ZnO synthesized. . .

Room temperature ferromagnetism and dielectric enhancement in nanocomposites ZnO doped with iron

“…Also, the secondary phase (ZnFe 2 O 4 ) formation is indicated in XRD, which is the main contribution to the observed ferromagnetism on studied samples due to the doping of Fe 3? ions [71].…”