Gd3+-Doping Effect on Upconversion Emission of NaYF4: Yb3+ Er3+/Tm3+ Microparticles

摘要

-NaYF microcrystals co-doped with Yb , Er /Tm , and Gd ions were synthesized via a hydrothermal method using rare-earth chlorides as the precursors. The SEM and XRD data show that the doped -NaYF form uniform hexagonal prisms with an approximate size of 600–800 nm. The partial substitution of Y by Gd results in size reduction of microcrystals. Upconversion luminescence spectra of microcrystals upon 980 nm excitation contain characteristic intra-configurational ff bands of Er /Tm ions. An addition of Gd ions leads to a significant enhancement of upconversion luminescence intensity with maxima at 5 mol % of dopant.