The first examples of X-ray phosphors, and C-band infrared emitters based on microporous lanthanide silicates

The synthesis and luminescence characterisation of microporous Tb3+ and Er3+ -silicates (Na(4)K(2)Ln(2)Si(16)O(38).10H(2)O, AV-9 materials) are reported. These solids possess a structure related to the structure of mineral montregianite and are the first examples of siliceous materials combining zeolite-like properties with X-ray induced luminescence and infrared emission. The photoluminescence (PL) integrated intensity of Tb-AV-9 is 60% of the integrated intensity of the Gd2O2S:Tb standard X-ray scintillator. The 1.54 mum emission of hydrated Er-AV-9 is strongly enhanced with dehydration at 553 K. Calcination of Er-AV-9 at 1123 K yields a glass exhibiting efficient infrared PL at room temperature. The I-4(13/2) --> I-4(15/2) integrated intensity of dehydrated Er-AV-9 and glass samples increases by a factor of ca. 2 and 2.2, respectively, when the temperature is raised from 75 to 300 K. (C) 2003 Elsevier B.V. All rights reserved.