New Pr3+ site in β-SiAlON red phosphor

Abstract Luminescent emission spectra and excitation spectra of Pr0.016Si5.9Al0.1O0.1N7.9 (β-SiAlON:Pr3+) were measured. Emission upon UV excitation consists of sharp lines peaked between 600 and 630 nm, related to the 1D2→3H4 and 3P0→3H6 transitions in Pr3+ ion. Two other group of lines peaked between 500 and 530 nm and between 640 and 680 nm are related to the 3P0→3H4 and 3P0→3FJ transitions, respectively. Excitation spectrum of the β-SiAlON:Pr3+ luminescence (observed at 641 nm and at 632 nm) consists of sharp lines in the spectral region 450–500 nm related to the 3H4→3P0, 3P1, 3P2 transitions and two broad bands peaked at 280 and 330 nm attributed to ionization of Pr3+. Emission obtained upon excitation at 330 nm band contains additional peaks besides earlier observed upon excitation at 280 nm band and under excitation in the 3H4→3P2 absorption region. These additional lines were attributed to the second site of Pr3+ (Wyckoff letter 2a) where Pr3+ ions occupy the interstitial positions of nine-fold coordinated by nitrogen/oxygen ions.