Regulation defect and Eu2+ luminescence via cation substitution in Ca2BO3Cl:Eu2+, M2+ (M = Sr and Ba) for white LEDs

Cation substitution was used as a method to discover new phosphor. Here, Eu2+ single doped single-phased warm white emitting phosphors Ca2BO3Cl:Eu2+, nM2+ (M = Sr and Ba) (CBL:Eu2+, M2+) were synthesized by controlling cations substitution systematically, and the crystal structure and luminescence property were analyzed. Ca2BO3Cl:Eu2+, nM2+ (M = Sr and Ba) exhibits a strong emission peak at 577 nm. With increase of cationic (Sr/Ba) concentration, the defect level occurs to move because of the crystal field of host changing, which causes the defect emission tuning from 428 to 401 nm. In this case, warm white light may be clearly generated by combining the blue emission (∼410 nm) and yellow emission (577 nm), which is observed for the first time in this kind of structure material.