Novel Processing for Softly Agglomerated Luminescent Y2O3: Eu3+ Nanoparticles Using Polymeric Precursors

Abstract

Synthesis of europium ion doped yttrium oxide (Y 2 O 3 :Eu 3{ ) phosphor nanoparticles using a relatively high molecular weight polyethylene glycol is reported. Y 2 O 3 : Eu 3{ materials could be prepared by simply heating in air provided that, watersoluble polymer be added into solutions containing metal nitrates. The polymer was ex pected to form carbonaceous materials around the produced primary particles to reduce the tendency of those particles to agglomerate. The carbonaceous materials could be removed by heating at higher temperatures, resulting in softlyagglomerated particles in the size range of 20100 nm. The eect of synthesis parameters on particle morphology, crystallinity, and photoluminescence properties was investigated.

Luminescent properties of PEG-added nanocrystalline YVO4:Eu3+ phosphor prepared by a hydrothermal method

“…The excitation spectrum consists of a broad band ranging from 225 to 340 nm and some sharp lines in the longer wavelength region. The former is mainly due to the absorption of the VO 4 3 À group, ascribed to charge transfer from O 2 À to the central V 5 + and the latter to f-f transitions within the Eu 3 + 4f 6 configuration with a 7 F 0 -5 L 6 (398 nm) transition as the most prominent group [11]. Furthermore, the emission spectra exhibited two weak bands of a magnetic dipole transition ( 5 D 0 -7 F 1,3 ) and other prominent peaks centered at 619 and 700 nm due to 5 D 0 -7 F 2,4 forced electric dipole transitions.…”

“…The europium emission of nanoparticles implies an energy-transfer mechanism from the excited absorbing groups to luminescent centers following the well-established thermally activated energy migration [2]. In principle, the activator (Eu 3 + ) luminescence quantum yield could benefit from efficient energy transfer, because the dopant may be excited even by distant absorbing groups (VO 4 3 À ) [16]. Therefore, the emission behavior of both the annealed sample and the PEG-assisted hydrothermally grown nanoparticles follow this thermally activated luminescence process.…”

“…Several strategies have been developed for dispersing these primary crystallites into nanophosphors. One representative approach entails the use of a water-soluble polymer, for example, polyethylene glycol (PEG), to produce nanophosphors via a polymer complex-processing method [4][5][6]. Using this method, a redox reaction between PEG and metal salts at elevated temperatures leads to the formation of nanocrystals.…”

Technology Innovation in the Nanoparticle Project

“…Y2O3: Eu 3 materials could be prepared by simply heating in air when a watersoluble polymer was added into a solution containing metal nitrates. 6) When the polymer was absent, flake particles above 2 micrometers in size were formed. A dramatic reduction in particle size occurred when the polymer was added to the precursor.…”

Synthesis of Oxide Particles Using a Polymer-Assisted Spray Pyrolysis Reactor, and a Percolation Explanation of Particle Separation

“…One quick method for the production of fine oxide particles is the simple heating of metallic precursors in a solution of high molecular weight polymers (HMWPs) (Abdullah & Okuyama, 2004;Abdullah et al, 2005a;2005b;2008a;2008b;Abdullah & Khairurrijal, 2008;Astuti et al, 2009a;2009b;2009c;Ogi et al, 2005). For example, in one study, nitrous metal was first dissolved in a solution of polyethylene glycol (PEG) solution and then put in a furnace in atmospheric air (an inert gas is not needed to make oxide particles).…”