Improved Cathodoluminescence of Y[sub 2]SiO[sub 5]:Ce-BAM:Eu Mixed Blue Phosphor

A strategy, which is very simple but very effective for controlling cathodoluminescence (CL) intensity of the blue phosphor at a low working voltage, is introduced. The key idea was to use the cathodoluminescence of Y 2 SiO 5 : Ce phosphor to additionally pump the photoluminescence of BaMgAl 10 O 17 : Eu (BAM) phosphor. The deep-blue or near-ultraviolet light, emitting from the cathodoluminescence of Y 2 SiO 5 : Ce phosphor, was found to efficiently excite again the BAM phosphor which then emits a new blue light via photoluminescence. Thus, the Y 2 SiO 5 : Ce ∕ BAM mixed phosphor had a higher emission intensity than that of the pure BAM phosphor as well as Y 2 SiO 5 : Ce one at a low accelerated voltage (800 V). The peak shape of Y 2 SiO 5 : Ce ∕ BAM mixed phosphor was nearly identical with that of BAM until the amount of Y 2 SiO 5 : Ce becomes 50 wt %. This result supported the concept that the deep-blue or near-ultraviolet light in the cathodoluminescence of Y 2 SiO 5 : Ce phosphor was efficiency reabsorbed by the BAM phosphor, thereby generating additional photoluminescence light. It was experimentally proved that the concept used in this work is a very simple but effective and useful way to improve the energy conversion efficiency of the phosphor.