Effect of temperature and doping on the structural and optical properties of copper oxide CuO nanopowders synthesized by sol-gel technique

In this work, pure, doped CuO nano-powders were prepared by the sol-gel deposition technique. In this preparation of the “CuO” powder, we used the precursor (CuCl2, 2H2O). We studied its structural, morphological, and optical properties. The annealing temperature effect on the size of CuO crystallites was also studied. The structural, microstructure, and optical absorption analyses for its nanoparticles were studied. X-ray diffraction (XRD), infrared absorption spectroscopy (IR),scanning microscopy (SEM),and UV-visible spectrophotometry were implemented. The X-ray diffraction analysis, therefore, revealed the presence of the monoclinic structure of CuO. The average size of the crystallites increases with the increase in the annealing temperature. Concerning nano-powders doped with ZnO, the grain size also increases with the rise in the annealing temperature and the percentage of ZnO added. The study of the optical properties of pure CuO powder has shown band gap values of around 3.88 eV and 3.89 eV.