Highly efficient low-voltage cathodoluminescence of LaF₃:Ln[sup 3+] (Ln=Eu[sup 3+], Ce[sup 3+], Tb[sup 3+]) spherical particles

Abstract

Spherical particles of rare-earth doped LaF₃ are synthesized through refluxing in glycerol/water media. The low-voltage cathodoluminescence of LaF₃ :Eu due to [sup 5]D[sub 0]→[sup 7]F₁ and [sup 5]D[sub 0]→[sup 7]F₂ transitions was found to be sensitive to the site that Eu[sup 3+] ions occupied. The luminous efficiency of LaF₃:Ce[sup 3+], Tb[sup 3+] with green emission is improved from 1.53 to 2.02 lm/W compared with LaF₃:Tb[sup 3+], due to the energy transfer processes from Ce[sup 3+] to Tb[sup 3+] ions. Our results suggest that the obtained spherical particles of rare-earth doped LaF₃ are promising as highly efficient low-voltage cathodoluminescent phosphors, which have received considerably less attention.