SILAR processing and characterization of bare and graphene oxide (GO) and reduced graphene oxide (rGO)-doped CuO thin films

In this research, bare, graphene oxide (GO) and reduced graphene oxide (rGO)-doped nanostructured copper oxide (CuO) thin films have been deposited on soda-lime glass substrates using low-cost and easy solution-based successive ionic layer adsorption and reaction (SILAR) method. The victoriously produced films were characterized to understand the effect of GO and rGO content on the crystalline structure, surface morphology, and optical properties of the CuO samples by different characterization methods. The obtained results showed that GO and rGO doping heavily affected the main physical characteristics of CuO nanostructures. XRD measurements confirmed the sharp, monoclinic CuO phase with the preferred orientation (002) and (112). The estimated crystallite size of samples is changed with GO and rGO doping as 7.63, 8.37, and 8.50 nm for the bare, GO, and rGO-doped CuO films, respectively. FE-SEM and SPM results exhibited that film morphology is influenced by the GO and rGO doping. The FTIR and Raman spectra of CuO have an ordinary stretching vibration mode of the metal-oxide bonds and the presence of GO/rGO led to the change of peaks of this structure. The optical bandgap energy of bare CuO was found to be 1.47 eV and it decreased to 1.32 eV as a result of rGO doping which is good sufficient for solar window applications. The sheet resistance value decreased with the GO doping from 7.87 x 10(9) to 2.72 x 10(9) omega/sq. The obtained results signify that the doping of GO and rGO in CuO thin films are responsible for the regulation of the main physical properties of nanostructured materials as electronic and optoelectronic materials.