Abstract
Calcium-doped ZnO (ZO-Ca) and undoped ZnO nanopowders were synthesized by the sol-gel method. The XRD results indicate that the structural properties of these samples presented hexagonal Wurtzite phase. In addition, the average crystallite size calculated is 37 and 44 nm for an undoped and doped sample, respectively. Further, impedance spectroscopy was investigated to study the calcium doping effect on the electrical behavior of ZnO nanoparticles. The decrease of the exponent s with increasing temperature suggests that the conduction mechanism predominant is the correlated barrier hopping (CBH). The complex impedance analysis of the ZO-Ca samples showed that at low frequency, there is a plateau that get reduced with a temperature which verifies the thermal activation of the conduction mechanism. The obtained results are interesting for understanding the effect of doping on the electronic transport mechanism which is unavoidable to explain the fundamental aspect in various technological applications.