Suppression of inner energy dissipation in Yb-doped NaErF_(4)upconversion nanocrystals through an energy cycling strategy

Suppression of the inner energy dissipation,related to the lattice phonons and inner defects,in lanthanide doped upco nversion luminescent materials remains a formidable challenge.Herein,we reveal an energy cycling strategy capable of suppressing the inner energy dissipation in lanthanide doped upconversion nanocrystals.Yb^(3+)ions were introduced in Er^(3+)heavily doped nanocrystals as an energy reservoir to compete with the inner energy dissipation.The detailed energy cycling processes between Er^(3+)activator and Yb^(3+)reservoir,responsible for the enhancement of Er^(3+)upconversion intensity,are proposed and further verified on the basis of spectral observations.The energy cycling strategy,with unique merits like facile and cost-effective preparation as well as broad scope of application,is highly valuable in lanthanide luminescent nano materials.