Preparation and Luminescence Properties of Y 2O 3: Eu 3+ Nanorods via Post Annealing Process

Abstract

Yttrium oxide doped with europium has a great prospective for FED and PDP phosphor application. In present study, the precursor of yttrium oxide hydroxide nitrate nanorod, which was prepared via hydrothermal reaction route using PEG-6000 as template from the starting Y(NO 3) 3 and KOH reactant system, was used to prepare Y 2O 3:Eu 3+ nanorod via a post annealing process during which the precursor with adjustable shape and size was transformed to final Y 2O 3: Eu 3+ product. XRD, field emission scanning electron microscopy (FE-SEM) and photoluminescence spectra (PL) were used to characterize the crystalline, morphology and luminescence properties of as-formed Y 2O 3: Eu 3+ products synthesized at different post annealing temperatures, respectively. The results indicate that grain morphology of obtained Y 2O 3: Eu 3+ product was nanorod with a mean diameter of about 40 ∼ 60 nm and length of about 500 ∼ 700 nm, the nanorod structure and morphology of obtained Y 2O 3: Eu 3+ product maintained during post annealing process and the size varied slightly with different annealing temperatures. Pure cubic Y 2O 3: Eu 3+ phase was formed and the size was the smallest at annealing treatment of 500 °C. Under the annealing temperature below 500 °C its diameter increased with increasing annealing temperature, and remained in a stable size when the annealing temperature was above 500 °C. The PL spectra of excitation spectra of Y 2O 3: Eu 3+ product show that it exhibits excitation band located at about 395 and 468 nm, respectively. Above two excitation bands could be ascribed to the transition 4f-4f of Eu 3+ ions in the Y 2O 3 host. On the other hand, the main emission peaks of the as-prepared products could be ascribed to the Eu 3+ ions transition from 5D 0 to 7F 2. Furthermore, the luminescent intensity was improved about three times when the annealing temperature increased from 500 to 1000 °C.