High efficiency and broadband blue-emitting NaCaBO3: Ce3+ phosphor for NUV light-emitting diodes

A blue-emitting phosphor, NaCaBO3: Ce3+, was synthesized by a solid-state reaction. The phosphor can be efficiently excited by near ultraviolet (NUV) light, and emits bright broadband blue light. The optimal Ce3+ concentration and its critical energy transfer distance were determined to be 0.01 and 38.0 Å. The photoluminescence excitation (PLE), emission (PL) spectra, and decay curves were measured to analyze the crystallographic occupancy sites of Ce3+ in the NaCaBO3 hosts. The composition-optimized NaCaBO3: 0.01Ce3+ exhibited high quantum efficiency of 75%. The results indicate that the phosphor NaCaBO3: Ce3+ could be served as a potential blue-emitting phosphor candidate for NUV LED application.