Growth of homogenous CuO nano-structured thin films by a simple solution method

▶ Average thicknesses of the plate-like nanostructures are 100 nm. ▶ CuO crystallized in monoclinic structure in ( 1 ¯ 1 1 ) and (1 1 1) directions. ▶ Ionization energies of the impurity levels are 0.30 eV and 0.32 eV. ▶ Band gap energies are 1.37 eV and 1.39 eV. This paper describes a simple, low temperature and cost effective solution method to synthesize homogenous cupric oxide (CuO) nano-structured thin films. By this method dense and continuous CuO films with good crystallinity can be prepared in a short time, e.g., in 15 min. The scanning electron microscopy illustrated that the synthesized CuO plate-like nanostructures have RMS thicknesses of 100 nm. The XRD measurements showed that the synthesized CuO nanostructures have a high crystallinity with monoclinic crystal structure preferentially in ( 1 ¯ 1 1 ) and (1 1 1) directions. From the temperature dependant dark electrical resistivity measurements the ionization energies of the impurity levels and thermal band gap energies of the films were calculated.