Highly enhanced upconversion luminescence in lanthanide-doped active-core/luminescent-shell/active-shell nanoarchitectures

摘要

We reported a new strategy to remarkably improve upconversion luminescence of Ln(3+)-doped nanoparticles via an active-core/luminescent-shell/active-shell engineering technique. By optimization of the structure of a NaGdF4:Yb@NaYF4:Yb/Er@NaGdF4:Yb sandwich-like nanoarchitecture, a significant enhancement of upconversion emission intensity was realized with the help of the synergistic actions of the suppression of Er-defect energy transfer and the efficient energy transfer from Yb3+ in both active-core and active-shell to Er3+ in the luminescent-shell layer.