Energy Transfer from Ce³⁺ to Eu²⁺ in LiSrBO₃ and Its Potential Application in UV-LED-Based White LEDs

Ce³⁺/Eu²⁺ codoped LiSrBO₃ phosphor is synthesized, and its luminescent characteristics are investigated. LiSrBO₃:Ce³⁺,Eu²⁺ phosphor exhibits varied hues from blue to white and eventually to yellow by resonance-type energy transfer from Ce³⁺ ion to Eu²⁺ ion and tuning the relative proportion of Ce³⁺/Eu²⁺ properly. Energy transfer mechanism in LiSrBO₃:Ce³⁺, Eu²⁺ phosphor is dominated by the dipole-dipole interaction, and the critical distance of the energy transfer is estimated to be about 2nm by both spectral overlap and concentration quenching methods. Under UV radiation, white light is generated by coupling 436 and 565nm emission bands attributed to Ce³⁺ and Eu²⁺ radiations, respectively.