Luminescence of Ce3+-doped Sr10(PO4)6S phosphors

The spectroscopic properties of a series of chalcogenide apatite phosphors, pure and Ce-doped Sr-10(PO4)(6)S, prepared by a high-temperature solid-state reaction technique, were investigated at different temperatures. The pure Sr-10(PO4)(6)S powder shows a broad blue emission peaking at 472 nm (2.63 eV), which results from self-trapped exciton (STE) in the host lattice with the wavelength at 271 nm (4.57 eV). The decay time is about several microseconds. Activator ion Ce3+ shows general f-d transition luminescence with a decay time of more than 20 ns. The activation energy E-A for thermal quenching of STE and Ce3+ luminescence was fitted.