Novel polyhedron-like t-LaVO4:Dy3+ nanocrystals: Hydrothermal synthesis and photoluminescence properties

Novel polyhedron-like LaVO4:Dy3+ nanocrystals (NCs) with tetragonal (t-) structure have been prepared via a facile hydrothermal route at 160 degrees C for 24 h. The as-prepared samples were characterized using powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and photoluminescence (PL) spectroscopy. High-quality and uniform polyhedrons with a mean length of 80 nm and a mean width of 60 nm could be easily obtained by varying reaction conditions. The effects of pH value, reaction time, and annealing temperature on the morphology and size of LaVO4:Dy3+ nanoparticle have been investigated in detail. The PL. measurements showed that polyhedron-like LaVO4:Dy3+ NCs exhibited improved luminescence properties compared to LaVO4:Dy3+ NCs with other shapes. In addition, the possible mechanism of polyhedron-like LaVO4:Dy3+ NCs was briefly proposed. (C) 2008 Elsevier B.V. All rights reserved.