Promoted reversible wettability transition by plasmonic effects at Ag/TiO2 heterointerface

We explore in this paper the photoinduced wetting/dewetting behaviors of silver/rutile heterointerfaces and demonstrate that silver nanoparticles can greatly increase the ultraviolet induced wetting and infrared induced dewetting transition rates. The results are interpreted based on the examination of the defect structures of the rutile surface before and after ultraviolet irradiation. The density functional theory calculation with the inclusion of the on-site Coulomb interaction reveals that the formation energy of an oxygen vacancy on the silver/rutile (110) interface is lower than that on the blank rutile (110) surface. We also discover that plasmonic nanostructures enable the partial wetting transition of the rutile (110) surface by irradiation with visible light at 473 nm and 532 nm. This work opens up a feasible route to the development of high-performance multifunctional materials via plasmonic nanostructures and defect engineering.