Abstract
Spherical NiO nanoparticles have been synthesized by a simple and modified solvothermal method using NiCl2 center dot 6H(2)O and urea. After the precursor was calcined in the air, NiO could be obtained. Structural, optical, and morphological characterizations were done by x-ray powder diffraction, ultraviolet-visible (UV-vis) spectroscopy, and scanning electronmicroscopy. Fourier-transform infrared (FTIR) studies show a broad absorption around 422-425 cm(-1) corresponding to a surface-active mode, indicating the nanocrystalline nature of the oxide. The values of some important physical parameters of material are determined, such as refractive index (n), dielectric constant (epsilon), ratio of molar volume (V-m) and molar refraction (R-m), and metallization criterion (M-(n)).