Effects of Cu and Mn dopings on the structural, optical, and magnetic properties of Zn0.98Fe0.02O nanopowders

This paper reports on the structural and magnetic properties of Zn0.98−xFe0.02(Cu/Mn)xO (x = 0.0 and 0.02) nanopowders synthesized using a solid-state reaction method. Ultraviolet–Visible spectroscopy measurements demonstrated that the bandgap increased in the Fe-doped ZnO and decreased in both the Cu- and Mn-doped Zn0.98Fe0.02O. Photoluminescence studies confirmed the formation of oxygen vacancies (VO) in all of the samples. The magnetization measurements revealed that the doping of Cu or Mn ions in Zn0.98Fe0.02O increased the saturation magnetization (Ms). The Ms value of the Cu-doped Zn0.98Fe0.02O is about five times larger than that of the undoped ZnO. The Ms value of the Mn-doped Zn0.98Fe0.02O is of a magnitude larger than that obtained for the Cu-doped Zn0.98Fe0.02O, and it is about one and a half times larger than the magnitude of the Zn0.98Fe0.02O and seven times larger than the magnitude of the undoped ZnO. We believe that the ferromagnetism is intrinsic, and it results from the interactions induced by the VO incorporated into the ZnO lattice.