Chromaticity-Tunable Emission of Sr[sub 3]AlO[sub 4]F:Ce[sup 3+] Phosphor: Correlation with Matrix Structure and Application in LEDs

Sr 3 − 2 x Ce x Na x AlO 4 F phosphors were synthesized by a high temperature solid-state reaction method, and their luminescence properties were investigated. Ce 3 + ions occupy two different Sr 2 + sites in these phosphors, and the different emissions derived from the two luminescent centers are discussed in terms of the matrix structure. The site occupancy and energy-transfer process give rise to the concentration-dependent luminescence behaviors, and the emission color may be tuned in a large color gamut from blue-green to yellow-green by controlling the Ce 3 + concentration. Because the phosphors exhibit a strong absorption in the range of near-UV to blue spectral region, the phosphors were utilized to fabricate the phosphor-converted light emitting diodes. The results show that the phosphors Sr 3 − 2 x Ce x Na x AlO 4 F have potential applications in light emitting diode (LED) devices.