Morphological and optical studies of zinc oxide doped MgO

This paper reports morphological and optical characterizations of sintered (ZnO)1−x(MgO)x composite materials. The effects of MgO doping content on these pellets properties have been analyzed. The SEM observations have shown rougher surfaces of the samples covered by grains having prismatic shapes and different sizes. From reflectance and absorption measurements, we have determined the band gap energy which tends to augment from 3.287 to 3.827 eV as the doping content increases. This widening of the optical band gap is explained by the Burstein-Moss effect which causes a significant increase of electron concentration (2.89 1018−5.191020 cm−3). In addition, the absorption coefficient, Urbach energy, optical constants (refractive index, extinction coefficient, dielectric constant) and dispersion parameters, such as E0 (single-oscillator energy), Ed (dispersive energy) were determined of the (ZnO)1−x(MgO)x composites and analyzed.