Facile synthesis and luminescence properties of monodisperse lutetium oxide nanostructures with adjustable particle sizes

Abstract

A variety of spherical lutetium based compounds with narrow size distribution and adjustable particle sizes have been synthesized by a novel route with ethylene glycol (EG) or ethanol as auxiliary solvent. The spherical Lu(OH)CO₃ precursors with adjustable particle sizes are firstly prepared by controlling the reaction conditions. After a heat treatment in air, the Lu₂O₃ products inherit the perfect morphology, good dispersity and uniformity except for the rougher surfaces and shrinkage in diameters, which result in the well-defined spherical Lu₂O₃ spheres with various diameters. The diameters of the spherical Lu(OH)CO₃ and Lu₂O₃ samples decrease gradually with increase of the volume ratio of EG or ethanol in solvent. By doping an appropriate amount of lanthanide activator ions (Ln³⁺) into the resulting Lu(OH)CO₃ and Lu₂O₃ host, the as-synthesized luminescent materials exhibit characteristic downconversion and upconversion emissions under UV or NIR excitation. In particular, the size-dependent luminescence performance of the phosphors is studied. Moreover, the LED devices fabricated by the as-obtained luminescent materials show bright characteristic multicolor emissions of Ln³⁺ ions, indicating the potential of the luminescent materials for LEDs and optoelectronic devices.