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Seminar Announcement: María Teresa Colomer Bas

posted Dec 6, 2015, 5:37 AM by Stefano Varas   [ updated Dec 6, 2015, 5:37 AM ]

Friday, 04 December 2015, 15:00
Sala Grande Palazzina B via alla Cascata 56/C

Effect of Tb3+ doping and Self-generated Pressure on the Crystallographic/Morphological Features and Thermal Stability of LaPO4∙nH2O Single-Crystal Nanorods

María Teresa Colomer Bas
Instituto de Cerámica y Vidrio, CSIC, C/Kelsen 5, 28049 Madrid, Spain

Tb3+-doped LaPO4∙nH2O single-crystal nanorods have been obtained by a simple and fast microwave-assisted hydrothermal synthesis. The effect of Tb3+-doping content (in the range 0‒20 mol.%) and autogeneous/self-generated pressure (in the range 2.3‒3.4±0.1 bar) on the crystallographic/morphological features and thermal stability of single-crystal nanorods of LaPO4∙nH2O was investigated. High-quality rhabdohane-type single-crystal nanords are obtained in all cases. However, their aspect ratio decreases with increasing self-generated pressure during the synthesis and with Tb3+ doping. In addition, it is shown that the Tb3+ solutes are incorporated into the LaPO4∙nH2O host, forming substitutional solid solutions with progressively smaller unit-cell volume but with identical thermal stability. It is also demonstrated that monazite-type single-crystal La1-xTbxPO4 nanorods can be obtained by calcining their rhabdophane-type La1-xTbxPO4∙nH2O counterparts at ~700 ºC in air. The influence of the aspect ratio of the nanorods on the PL properties is now in progress.

Keywords: Tb3+, LaPO4, hydrothermal synthesis-assisted by MWs, morphology, structure, photoluminescent properties.

Stefano Varas,
Dec 6, 2015, 5:37 AM