Search

Abstract  The photoluminescence (PL) spectra, excitation spectra, and PL decay curves of natural, heat-treated, and γ-ray-irradiated thenardites from Ai-Ding Salt Lake, Xinjiang, China, were studied. The natural thenardite under 300 nm excitation showed milk-white luminescence, and the PL spectrum consisted of an extremely broad band with a peak located at approximately 509 nm, spreading over a wide range of UV and visible wavelengths. The excitation spectra, obtained by monitoring the luminescence at 530 nm, consisted of a broad band with a peak located at approximately 235 nm and a flat band spreading over a wide range of UV and visible wavelengths. The PL decay curve of natural thenardite consisted of a fast-decay component with a lifetime of less than 0.1 μs and a slow-decay component with a half-decay time of approximately 0.4 s. The heat treatment of thenardite at 900°C for 20 min reduced the luminescence efficiency to 1/100. The γ-ray irradiation of thenardite reduced the luminescence efficiency to approximately half. [ABSTRACT FROM AUTHOR]