Optical, electrical and microstructural studies of monoclinic CuO nanostructures synthesized by a sol-gel route

We have reported on the synthesis of CuO nanostructures via a simple sol-gel approach with high yield at low cost by the reduction of aqueous solutions of Cu(NO 3 ) 2 and Na 2 NO 3 . Synthesized nanostructures were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), fluorescence spectroscopy, Raman scattering and UV-Vis-NIR spectroscopy. Structural studies revealed that the prepared CuO nanostructures were polycrystalline in nature with monoclinic structure. The crystallite size of CuO nanostructures was estimated to be ∼10 nm using Debye-Scherrer's formula. The uniform and nanoregime grains were observed in SEM micrographs. The optical band gap value was estimated to be 1.2 eV using Tauc's plot. The Raman scattering investigations revealed A g and B g mode peaks at 278 cm −1 , 332 cm −1 and 618 cm −1 , respectively. A g and B g mode vibration peaks are observed in the Raman spectrum with a lower optical band gap of 1.2 eV.