Self-Activating Strontium Orthoborate Blue Phosphors Induced by Cation and Anion Deficiencies and Their...

Self-activating blue-light-emitting strontium orthoborate phosphors, viz., Sr₃B₂₊O₆₊₃ and Sr₃B₂₊O₆₊₃ (x ranges from -0.3 to 0.1), were obtained by varying the number of BO_3/2 and anion deficiencies. The integrated intensity observed from the oxygen 1s profile obtained via X-ray photoelectron spectroscopy indicated the relative concentrations of the oxygen vacancies in the Sr₃B₂₊O₆₊₃ (x = 0, -0.1, and -0.3) and Sr₃B₂O_6-δ phosphors. The structures of Sr₃B₂O₆, Sr₃B_2.1O_6.15, Sr₃B_1.9O_5.85, and Sr₃B₂O_6-δ with crystal orientations were analyzed based on high-resolution synchrotron powder X-ray diffraction data. A mixture of rare-earth-free blue Sr₃B₂O_6-δ and yellow Sr_2.45Ba_0.5Na_0.05Al_0.95Sn_0.05O_4-αF_1-δ phosphors, incorporated on a 315 nm UV-LED chip, can generate a white-light UV-LED.