Plasmon-enhanced luminescence of Ag@SiO2/β-NaYF4:Tb3+ nanocomposites via absorption & emission matching

Nanocomposites attaching ligand-free β-NaYF₄:Tb³⁺ nanoparticles (NPs) on Ag@SiO₂ nanospheres were fabricated in the water solution. In the nanocomposites, the emission intensity of β-NaYF₄: Tb³⁺ NPs is greatly enhanced (3.9 times) by Ag@SiO₂ nanospheres while the shell thickness is 35 nm, which is owing to localized surface plasmon resonance (LSPR) via both of absorption and emission matching. A finite-difference time-domain simulation is employed to demonstrate the near field distribution of LSPR and its effect on Tb³⁺ emission. The novel nanocomposites have wide potential applications, such as photocatalysis, false proof mark, optical sensors and solar cells.