Luminescence properties and energy transfer of novel Bi3+ and Mn2+-co-activated Y3Ga5O12 single-component white light-emitting phosphor

Abstract

A series of novel Y₃Ga₅O₁₂:Bi³⁺,Mn²⁺ phosphors with controllable luminescence have been synthesized and their photoluminescence characteristics have been studied in detail with the purpose of developing a single-component white light-emitting phosphor suitable for pc-WLEDs. The Bi³⁺ singly-doped phosphor shows an intense blue–green emission, while the Mn²⁺-doped phosphor presents a narrow red emission with a FWHM of 59 nm, which is comparable to the previously reported nitride red phosphor Ca[LiAl₃N₄]:Eu²⁺. When Bi³⁺ and Mn²⁺ were co-doped into the Y₃Ga₅O₁₂ matrix, effective energy transfer from the Bi³⁺ to Mn²⁺ ions was observed. Subsequently, a single-component warm white light-emitting phosphor was obtained by adjusting the doping ratio of Bi³⁺ and Mn²⁺ and by utilizing the energy transfer from the Bi³⁺ to Mn²⁺ ions. Moreover, the thermal quenching properties show that the prepared Y₃Ga₅O₁₂:Bi³⁺,Mn²⁺ samples possess good thermal stability of luminescence. Finally, a WLED device with a high R_a of 90, a low CCT of 3908 K, and a CIE color coordinate of (0.3503, 0.3158) has been fabricated using the synthesized phosphor. The results indicate that Y₃Ga₅O₁₂:Bi³⁺,Mn²⁺ phosphors are potential candidates as single-component white light emission phosphors applied in WLEDs. Moreover, this strategy is also conducive for the design of novel white light emission phosphors for pc-WLEDs.