Zero Concentration Quenching LiCaLa(MoO4)3:Eu3+Red Phosphors with Scheelite structure for white LEDs

Abstract

A series of red-emitting phosphors with scheelite structure is explored for solid-state lightings. The powder XRD pattern reveals that all the compositions crystallize in a tetragonal structure with space group IA1/a. The PLE and PL study reveal that the phosphor composition showed broad absorption (due to O-Mo, O-Eu (CT band) and narrow band absorption bands (due to 4f-4f electronic transition of Eu3+ ion). The PL emission reveals that the phosphors showed extremely narrow band emission at 615nm (FWHM 5-10 nm) with high color purity. The dominant red line implies that the Eu3+ ion occupies the non – centrosymmetric site. The selected phosphors showed good quantum yield and excellent thermal stability. Li Ca Eu (MoO4)3 phosphor conjugated with near UV LED as well as a yellow dye, the red and white LED were fabricated and the EL emission showed excellent red and white color with appropriate CIE values. The detailed results will be presented and discussed.