A Novel Highly Efficient Host-Sensitized Red Emitting (Ba2YV3O11 : Eu3+) Phosphor for Hybrid White LEDs

The present investigation focused on the sequence of Eu3+ activated red-emitting vanadate phosphor for the high performance white LEDs. The blue emitting host lattice (Ba2YV3O11) and red emitting Ba2YV3O11 : Eu3+ phosphors were synthesized by the conventional solid-state method and studied their optical properties in details. The host lattice and Eu3+ activated red phosphors were crystallized in the monoclinic crystal system. The Ba2YV3O11 emission was found in the bluish-green region (444 and 512 nm, which corresponds to the T-3(2)->(1)A(1) and T-3(1)->(1)A(1) transitions), and the Eu3+ activated phosphors (Ba2Y1-xEuxV3O11, x=0-1, insteps of 0.1) display intense red emission at 618 nm due to the D-5(0)-> F-7(2) electric dipole (ED) transition. The concentration quenching was observed at x=0.6, the detailed energy transfer mechanism was also explored. Thermal stability of the Ba2Y0.4Eu0.6V3O11 red phosphor retains the similar to 60 % emission intensity at 423 K, and the internal quantum efficiency (IQE) was found to be 30 %. The red and white LEDs were fabricated by using the synthesized red phosphor with the combination of near UV LED (n-UV), the white LED showed white emission with CIE is x=0.359; y=0.395; higher CRI (89) and low CCT (4693 K) values. These results prescribe that the presently synthesized phosphor can act as a suitable red-emitting component in hybrid white LEDs.