LAUSR

Abstract The development of Eu3+-doped red phosphors with high absorption in near UV region is of great significance for application in warm white LEDs and remains a tremendous challenge owing to the special electronic structure of rare earth ions. In the present work, a novel BaBi2(MoO4)4:Eu3+ red phosphor were prepared, which exhibits high purity red emission with broad excitation band ranging from 200 to 400 nm, and have a high absorption. Raman analysis and DFT calculations certified that the broad excitation band originated from the characteristic transition absorption of Bi3+ ions. The optimum doping concentration of Eu3+ ions in BaBi2(MoO4)4 was determined to be as high as 50%. The luminescence intensity of BaBi2(MoO4)4:Eu3+ is much higher than that of commercial Y2O3:Eu3+ either under 365 nm or 395 nm excitation. More importantly, the covalence degree has a greater impact on the intensity ratio of electric dipole transition 5D0-7F2 and the magnetic dipole transition 5D0-7F1 (abbreviated as R/O) than the local symmetry around Eu3+ sites. This work presents a strategy to develop high-performance Eu3+-doped red phosphors with high absorption and brightness and provide a reference in exploring other rare earth doped phosphors.