High brightness and precise adjustment of multicolor-tunable luminescence of Lu2GeO5:Tb3+, Eu3+ phosphors for white LEDs

High brightness and precise adjustment of luminescence colour of phosphors are two main targets in the research of phosphor-converted white LEDs. However, few feasible strategy can be employed to achieve the multicolor-tunable luminescence under the premise of maintaining high quantum efficiency. Here, we demonstrate a high-efficiency energy-transfer process from Tb³⁺ to Eu³⁺ ions with a higher luminescent quantum efficiency (64.5% and 53.4%, respectively), and green-red multicolor emission in Lu₂GeO₅ host via varying the doping content of Tb³⁺ and Eu³⁺ ions. Besides, Lu₂GeO₅:Tb³⁺, Lu₂GeO₅: Eu³⁺ and Lu₂GeO₅: Tb³⁺, Eu³⁺ all exhibit weak thermal quenching which ensures the stable use of white LED device in the high temperature environment. This paper provides a novel multicolor-tunable phosphor with high brightness, efficient energy transfer and weak thermal quenching, which presents a potential application for UV-converted white LEDs.