Effects of lithium doping on: microstructure, morphology, nanomechanical properties and corrosion behaviour of ZnO thin films grown by spray pyrolysis technique

Li-doped ZnO thin films were prepared on glass substrate by a chemical spray pyrolysis method, in the temperature of 460 degrees C. The effects of Li content on the microstructural, morphological and mechanical characteristics of the doped (ZnO:Li) thin films were also examined. The XRD study showed a sharp preferred c-axis orientation and showed that (ZnO:Li) films have a wurtzite structure and grow principally along the c-axis orientation with a preferred orientation (002). The film morphology was examined by (AFM) and (SEM). Results of SEM observations showed that sprayed thin films, exhibited uniform and harmonious texture. Furthermore, ZnO:Li thin films revealed uniform and spherical shaped crystallites with an approximate medium size of 200nm. AFM characterization demonstrated an amelioration of the surface roughness of the ZnO:Li thin films. The mechanical characteristics of ZnO:Li thin films have been investigated by the nano-indentation experiment. It has been found that the addition of lithium enhances the hardness and Young's modulus. On the other hand, the corrosion behaviour of Li-doped thin films is examined in chloride solutions. The electrochemical experiments confirmed that the lithium doping could ameliorate the anti-corrosion performance.