Preparation and Optical Properties of new high temperature phase of Eu₂O₃ doped Y₂WO₆ red phosphor

Abstract

0-40 mol% Eu₂O₃ doped Y₂WO₆ red phosphors were prepared by solid-state reaction. The samples fired at the range of 1673-1973 K for 2h in air were mostly a single phase except for non-doped ones. XRD revealed the crystal structure of Eu₂O₃-activated ones were similar with Nd₂WO₆ (PDF #72-1867) type structure. That is new high temperature phase was considerable amount of yttria doped Eu₂WO₆ (C2/c), not europia doped Y₂WO₆ (high temperature modification of P2₁2₁2₁). Best composition was about 25 mol% europia doped one fired at 1923 K. Emission spectra (lambda_ex.= 393 nm) showed strong peaks of 614 and 611 nm. Excitation spectra (lambda_em.= 614 nm) did strong peaks of 393, 464 and 535 nm.