Research On Rare Earth Doped Fluoride-based Up-conversion Luminescent Materials

Rare-earth doped fluoride-based upconversion luminescent materials have received extensive attention due to their low phonon energy and high luminous efficiency.In this dissertation,PbF₂:Er³⁺,Yb³⁺,PbF₂:Ho³⁺,Yb³⁺,PbF₂:Ho³⁺,Er³⁺,Yb³⁺ and lead fluoride solid solution based upconversion luminescent materials doped with Er³⁺/Yb³⁺,Ho³⁺/Yb³⁺ and Ho³⁺/Er³⁺/Yb³⁺ were synthesized by high-temperature solid-state reaction method.The phase structure and luminescent properties of the samples were analyzed by XRD and emission spectra.The optimal preparation conditions were obtained as follows: the sintering temperature was 570 ?and the holding time was 1.5 h.This work has researched the upconversion luminescence performance of the Er³⁺ and Ho³⁺ activator ions,discussed the upconversion luminescence mechanism of Er³⁺,Ho³⁺ and Ho³⁺/Er³⁺ sensitized by Yb³⁺ ions directly,and investigated the effect of different Yb³⁺ doped concentrations on the luminescent properties of the samples.In addition,LaF₃ and BaF₂ were introduced into the host to prepare the composite lead fluoride based upconversion luminescent materials,and the effects of Bi³⁺,La³⁺ and Ba²⁺ on the structure and luminescent properties of the samples were investigated.Finally,an upconversion material with strong visible light emission excited at 1064 nm was obtained.