Luminescence and energy transfer of warm white-emitting phosphor Mg2Y2Al2Si2O12:Dy3+,Eu3+ for white LEDs

Abstract

A series of Mg₂Y₂Al₂Si₂O₁₂:Dy³⁺,Eu³⁺ phosphors were synthesized by the solid-state method. The luminescent properties and crystal structures of the Mg₂Y₂Al₂Si₂O₁₂:Dy³⁺,Eu³⁺ phosphors were analyzed. The XRD results show that the synthesized Mg₂Y₂Al₂Si₂O₁₂:Dy³⁺,Eu³⁺ phosphors are of pure phase. Mg₂Y₂Al₂Si₂O₁₂:Dy³⁺ can emit blue and yellow light under 367 nm light excitation; when doped with Eu³⁺, there is an obvious energy transfer from Dy³⁺ to Eu³⁺, and warm white light can be realized by adjusting the concentrations of Dy³⁺ and Eu³⁺ in Mg₂Y₂Al₂Si₂O₁₂. A warm white LED device was fabricated by combining Mg₂Y_1.88Al₂Si₂O₁₂:0.05Dy³⁺,0.07Eu³⁺ and a UV LED chip (370 nm) under a voltage of 3.2 V and current of 5 mA, the characteristics of the white LED being CIE = (0.4071, 0.3944), CCT = 3500 K and CRI = 91.3.