First principle and experimental investigations of monodispersed Au plasmonic nanoparticles on TiO2

Abstract

Plasmonic nanostructures play an important part in improving the light absorption of semiconductors that are feasible for photovoltaic and other optical devices. In this context, we have synthesized TiO2 thin films with monodispersed Au nanoparticles. These metallic nanoparticles act as plasmonic structures over the smooth semiconductor surface thereby enhancing their properties. X-ray diffraction was done to confirm the formation of the rutile phase while electron microscope images reveal the presence of Au nanoparticles over the entire surface of TiO2 film. Electronic properties were performed to determine a direct bandgap of 2.8 eV which was reduced significantly to 0.3 eV. Thermoelectric calculations were performed to explore the various temeperature dependent physical properties. Optical properties were also enhanced as high values of optical absorption and refractive index were obtained for TiO2 thin film with monodispersed Au nanoparticles.