A study on the structure transformation and luminescence of Eu(III) titanate nanotubes synthesized at various hydrothermal temperatures

Eu(III) titanate (Eu2Ti2O7) nanotubes have been successfully synthesized from sheet titanate (NaEuTiO4) by hydrothermal method at various reaction temperatures ranging from 110 to 150 degrees C. With increasing hydrothermal temperature, the morphology varied from two-dimensional nanosheets to one-dimensional nanotubes, which is owing to curling-up movement of nanosheets. At 150 degrees C, nanosheets transformed to tube-like structure on the whole. The inner diameters of Eu(III) titanate nanotubes are 30-40 nm and the wall of nanotubes is well crystallized multi-wall structure. The fluorescence properties of products hydrothermally synthesized at various temperatures have been investigated. The results indicate that when the hydrothermal temperature is 150 degrees C, the nanotubes obtained can be effectively excited by 395 nm light, and exhibit strong red emission around 616 nm. (C) 2009 Elsevier B.V. All rights reserved.