Asymmetric optical properties of photocatalytically deposited plasmonic silver nanoparticles

Ag nanoparticles deposited and grown photocatalytically for a sufficient period of time on a TiO 2 thin film scatter blue light and reflect reddish light when the particles are irradiated directly ( i.e. front incidence). On the other hand, they scatter reddish light and reflect blue light when the particles are irradiated through the TiO 2 film ( i.e. back incidence). The asymmetric optical behaviour is attributed to the asymmetric plasmon resonance, for which a sufficient height and a sufficient width at the top and the bottom of the Ag nanoparticles are important. Plasmonic Ag nanoparticles deposited and grown photocatalytically for a sufficient period of time on a TiO 2 thin film scatter blue or reddish light for the front or back incidence, respectively.