Effect of silver coating on the optical, morphological, PL and crystal structure of Ag– TiO2 thin films

In this research work, Ag– TiO2 thin films were deposited on microscope glass slides by spray pyrolysis and thermal vacuum evaporation combination techniques. The effect of substrate temperature and silver doping on crystal structure, surface morphology, hydrophilicity, hydrophobicity, and optical properties of the prepared thin layers were investigated by various techniques such as XRD, AFM, SEM, optical and photoluminescence spectroscopy. The results show the root mean square roughness deviation of pure TiO2 films decreased and the water contact angle increased with increasing of substrate temperature as well as silver thickness in the visible range. On the other hand, hydrophilicity nature of Ag–TiO2 layers raised with increase in the time of UV radiation. The optical absorption increased with silver doping due to collective oscillation of free electrons of small noble nanoparticles. The attained results indicate that the optical absorption increases with silver doping, because the radiated photon was trapped by silver nanoparticles in the TiO2 layers and so increases optical absorption. Anatase phase was dominant crystalline phase in all the prepared samples which is the best phase in photo catalyst and self-cleaning applications.