Design of a Bismuth-Activated Narrow-Band Cyan Phosphor for Use in White Light Emitting Diodes and Field Emission Displays
Shanshan Ye, Hai Liu, Yijie Wang, Jiao Lin, Kun Zhong, Jianyan Ding, Quansheng Wu
Abstract
To overcome the problem that Bi3+-activated phosphors suffer from, it is an urgent need to realize narrow-band light emission of Bi3+-activated phosphors, which not only improves their luminescence characteristics, but also increases their competitiveness with rare earth-activated commercial phosphors. In our work, a novel Bi3+-activated narrow-band cyan phosphor has been achieved in a highly condensed and symmetrical crystal structure of Ca3Lu2Ge3O12, and its full width of half-maximum (fwhm) of the emission band reaches 47 nm. The result indicates that Bi3+-activated Ca3Lu2Ge3O12 is comparative to the commercial green phosphor β-sialon: Eu2+ (fwhm ≈ 55 nm), and its strong excitation band locates at 390 nm, implying that Ca3Lu2Ge3O12: Bi3+ can be well excited by near-ultraviolet (NUV) LED chips. Furthermore, Ca3Lu2Ge3O12: Bi3+ possesses promising cathodoluminescence properties accompanied by good antiaging characteristics. The fascinating PL and CL properties of Ca3Lu2Ge3O12: Bi3+ have been proved to relate to their garnet-type structure; thus, the structure–property relations of Bi3+-activated Ca3Lu2Ge3O12 were discussed in detail in this work, which may provide an effective way for exploring better Bi3+-activated phosphors for use in WLEDs and FEDs.