Luminescence study on Eu3+ doped Y2O3 nanoparticles: Particle size, concentration and core-shell formation effects

Abstract

Nanoparticles of Eu3+ doped Y2O3 (core) and Eu3+ doped Y2O3 covered with Y 2O3 shell (core-shell) are prepared by urea hydrolysis for 3 h in ethylene glycol medium at a relatively low temperature of 140 °C, followed by heating at 500 and 900°C. Particle sizes determined from x-ray diffraction and transmission electron microscopic studies are 11 and 18 nm for 500 and 900°C heated samples respectively. Based on the luminescence studies of 500 and 900°C heated samples, it is confirmed that there is no particle size effect on the peak positions of Eu3+ emission, and optimum luminescence intensity is observed from the nanoparticles with a Eu3+ concentration of 4-5 at.%. A luminescence study establishes that the Eu 3+ environment in amorphous Y (OH)3 is different from that in crystalline Y2O3. For a fixed concentration of Eu 3+ doping, there is a reduction in Eu3+ emission intensity for core-shell nanoparticles compared to that of core nanoparticles, and this has been attributed to the concentration dilution effect. Energy transfer from the host to Eu3+ increases with increase of crystallinity. © IOP Publishing Ltd.