title: Tunable emission from blue to white light in single-phase Na(0.34)Ca(0.66-x-y)Al(1.66)Si(2.34)O8:xEu2+,yMn2+ (x = 0.07) phosphor for white-light UV LEDs.
abstract: A series of single-phased emission-tunable Na(0.34)Ca(0.66)Al(1.66)Si(2.34)O(8):Eu(2+),Mn(2+) phosphors were successfully synthesized by a wet-chemical synthesis method. Photoluminescence excitation (PLE) spectra indicate that the phosphor can be efficiently excited by UV radiation from 250 to 420 nm. Also, NCASO:Eu(2+),Mn(2+) phosphor exhibit a broad blue emission band at 440 nm and an orange emission band at 570 nm, which originate from Eu(2+) and Mn(2+) ions, respectively. Therefore, overall emission color can be tuned from blue to white by increasing the concentration of Mn(2+) ions in the host lattice utilizing energy transfer from Eu(2+) to Mn(2+) ions. This energy transfer phenomenon was demonstrated to be a resonant type through dipole-dipole interaction determined with the help of PL spectra, decay time measurement, and energy transfer efficiency of the phosphor. These results indicate that NCASO:Eu(2+),Mn(2+) can be a promising single-phased white-emitting phosphor for white-light UV LEDs.
authors.affiliation: Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea.
authors.forename: Ga-yeon
authors.initials: GY
authors.lastname: Lee
authors.forename: Won Bin
authors.initials: WB
authors.lastname: Im
authors.forename: Artavazd
authors.initials: A
authors.lastname: Kirakosyan
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Cheong
authors.forename: Ji Yeon
authors.initials: JY
authors.lastname: Han
authors.forename: Duk Young
authors.initials: DY
authors.lastname: Jeon
mesh_terms: D003116:Color; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008029:Lighting / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*; D012666:Semiconductors; D014466:Ultraviolet Rays