Recently,considerable attention has been paid to the synthesis and research of various rare-earth(RE) doped fluoride nanomaterials because of their high refractive index and appropriate phonon energy,which have potential applications in optics,optoelectronics,microelectronics,and tribology[1].
This paper reports that hexagonal-phase LaF3:Yb30.20,Er30.02 and LaF3:Yb30.20,Tm30.02 nanocrystals (NCs) were synthesized via a hydrothermal method.The transmission electron microscopy,selected area electron diffraction,powder x-ray diffraction,and thermogravimetric analysis are used to characterize the NCs.Under 980 nm excitation,the Yb3/Er3 and Yb3/Tm3 codoped NCs colloidal solutions present bright green and blue upconversion fluorescence,respectively.These NCs show efficient infrared-to-violet and infrared-to-visible upconversion.The upconversion fluorescence mechanisms of LaF 3:Yb30.20,Er30.02 and LaF3:Yb30.20,Tm30.02 NCs are investigated with a 980-nm diode laser as excitation source.
