Synthesis and Luminescence Properties of Cube-Structured CaSnO[sub 3]∕RE[sup 3+](RE=Pr,Tb) Long-Lasting Phosphors

Uniform and cube-structured RE3+ (RE=Pr,Tb) -doped CaSn O3 phosphors have been successfully synthesized by a two-step approach including the room-temperature synthesis of CaSn (OH)6 precursors with the help of cetyltrimethylammoniumbromide surfactant and then converted to CaSn O3 by calcination at 750°C. The decomposition process of the CaSn (OH)6 precursor, crystallization, and morphology of the as-synthesized CaSn O3 phosphors have been investigated using thermal analysis, X-ray diffraction, and scanning electron microscopy. Furthermore, luminescence properties of CaSn O3 RE3+ (RE=Pr,Tb) phosphors, including photoluminescence, fluorescence lifetime, afterglow decay, and thermoluminescence, are also systematically discussed in this paper. The as-synthesized Pr3+ and Tb3+ doped CaSnO3 phosphors show intense luminescence under ultraviolet excitation. Moreover, the afterglow emission from CaSn O3 RE3+ (RE=Pr,Tb) phosphors lasts for more than 3 h after the ultraviolet irradiation source has been removed. Both the fluorescence and afterglow decay curves of the CaSn O3 RE3+ (RE=Pr,Tb) phosphors contain one fast decay component and another slow decay process. Thermoluminescence spectra indicate that the incorporation of RE3+ ions into the CaSn O3 host produces suitable trapping centers, which are the origin of the long-lasting phosphorescence phenomenon in this kind of material at room temperature. © 2007 The Electrochemical Society.