Influence of Ni and Sr on the structural, morphological and optical properties of ZnO synthesized by sol gel

Abstract

ZnO nanoparticles doped and co-doped with Ni and Sr were synthesized by the sol gel method. Rietveld refinement indicated the single phase of ZnO for all the samples and suggests that the variations in structural parameters are dependent on the ions type. Fourier transform infrared studies showed the functional groups and chemical bonding of ZnO and confirmed the replacement of Zn by Ni and Sr ions. The micrographs showed particles with clusters shapes and different sizes. Photoluminescence measurements show a shift in near band edge UV emission, from 380 to 384 nm for doped and co-doped samples. Additionally, the Zn substitution by Ni and Sr ions minimizes the intrinsic defects in the ZnO structure. The optical study showed that the replacement of Zn by Ni decreases the band gap, whereas the substitution by Sr increases it. For co-doped samples, this value depends on the dopant concentration and the ions type. This work contributes to the understanding of optical properties for the ZnO nanoparticles co-doping with Ni and Sr, which may be important for future applications.