Seminar Title
Design and synthesis of novel red/orange-red emitting phosphor with (LiCaLa(MoO4)3:RE3+, RE = Eu, Sm) with Scheelite structure for Solid state lighting applications.
Seminar Type
Progress Seminar
Speaker Name
Priyansha Sharma ( Rollno : 518cy1018)
Speaker Type
Seminar Room, Chemistry Department.
Date & Time
29 Sep 2022 4 PM
Prof. Jaya Prakash Madda

Novel oxide based red and orange-red phosphor with negligible concentration quenching is bottle neck for the solid state lightings. In this context, a series of red, orange-red LiCaLa1-xEux(MoO4)3 and orange-red  LiCaLa1-xSmx(MoO4)3 emitting phosphors were synthesized and studied their optical properties. Systematically, the photoluminescence (PL) study reveals that the Eu3+ substituted phosphor emits red light due to (5D0-7F2) transition with zero concentration quenching. The Photoluminescence excitation (PLE) and PL study reveal that the phosphor composition showed broad absorption (due to O-Mo, O-Eu (Charge Transfer bands) and narrow band absorption bands (due to 4f-4f electronic transition of Eu3+ ion). The PL emission also reveals that the phosphors showed extremely narrow band emission at 615 nm (FWHM 5-10 nm) with high color purity. The dominant emission of red line implies that the Eu3+ ion occupies the non&ndashcentrosymmetric site. Whereas Sm3+ activated phosphor showed deep orange-red emission due to (4G5/2-6H9/2). All the compositions are crystallized in scheelite structure having tetragonal structure and I41/a space group. The red light emitting diodes (LEDs) were designed for the LiCaEu2.0(MoO4)3 red phosphors with the near ultraviolet (NUV) LED chip. White LED also been fabricated by conjugating the blue LED with yellow dye + red phosphor and the LED which shows CCT (4762 K), CRI (81%), CIE (0.34, 0.33). The detail results will be presented and disused.