The effect of solvent and temperature on the optical and structural properties of the nickel oxide and Cu-doped nickel oxide nanoparticles

Abstract

In the current work, nickel oxide (NiO) and copper-doped nickel oxide (Cu-NiO) nanoparticles were prepared by co-precipitation method. The effect of Cu doping on the structural and optical features of NiO nanoparticles and the effect of solvent and temperature on the optical and structural properties of nickel oxide and Cu-doped nickel oxide nanoparticles were studided by X-ray diffraction (XRD), ultraviolet-visible (UV-Vis) spectroscopy, fourier transform-infrared (FT-IR) spectroscopy and vibrating-sample magnetometer (VSM) technique. The XRD analysis condirmed that the Cu-doped nickel oxide have a cubical structure and showed that the crystalline size increased with the increase of temperature. The optical absorption spectra of the structures illusterated a blue-shift with decreasing in crystal size so that the energy gap of nickel oxide decreased with increasing temperature. Subsequently, in the presence of propranol and without ethylene glycol, the Cu-doped NiO band gap was the lowest and with the applying of ethanol and ethylene glycol was the highest amount. Magnetization property study of the nanoparticles performed at room temperature confirmed the weak ferromagnetic behavior of Cu-doped NiO nanoparticles before calcinations. The magnetization in the magnetic hysteresis loop indicated that nanoparticles have super paramagnetic property after calcination.