| 초록 |
In this study, Eu2+ activated Sr1-xCaxSe alkaline earth selenide phosphors were obtained by ultrasonic spray pyrolysis. The spray solutions were prepared using Sr(NO3)2, Ca(NO3)2, SeO2 (Aldrich, 99.999%), and Eu(NO3)3•5H2O dissolved in D.I water with 0.1M of total concentration . The formation of particles was occured at 650oC, and collected particles were sintered at 950oC for 4hr under H/N (5/95) reduction atmosphere. The prepared Sr1-xCaxSe:Eu2+ exhibited the uniform spherical shape with the submicron about 800-900nm in diameter. The Sr1-xCaxSe:Eu2+ maintained cubic structure regardless of Sr:Ca ratio, however, the emission band was changed from 561 to 607nm with increasing Ca2+ ratio. The detailed structural and luminous properties were investigated by SEM, XRD, and Photoluminescence (PL). The white LED was fabricated by combining 460nm LED chip with prepared alkaline earth selenide. The charactertic of white LED was analyzed by measuring luminous efficacy, CRI, CCT, and CIE. |
