Improved Energy Transfer between Ce3+and Tb3+Ions at the Interface between Y2Sn2O7:Ce3+,Tb3+Nanoparticles and Silica

Abstract

Very small spherical nanoparticles (size in the range of 2−5 nm) of Y2Sn2O7 doped with both Ce3+ and Tb3+ were prepared by the urea hydrolysis of Y3+, Sn4+, Ce3+, and Tb3+ in ethylene glycol medium at 150 °C followed by heating at 700 °C. These nanoparticles exhibit very poor energy transfer between Ce3+ and Tb3+ ions and associated luminescence due to the combined effect of centrosymmetric D3d environment around the lanthanide ions and quenching of the lanthanide ion excited state due to the vibrations of surface hydroxyl groups present on the nanoparticles. However, the energy transfer and associated luminescence can be significantly improved after dispersing the nanoparticles in silica matrix. On the basis of the detailed steady-state and time-resolved luminescence studies, it has been established that a significant amount of Ce3+ and Tb3+ ions migrate from Y2Sn2O7 host to both the silica matrix and the interface region between silica and Y2Sn2O7 nanoparticles. Improved energy transfer from Ce3+ to Tb3...