Study of White Light Emission from Europium (III) Doped Gadolinium Oxide Phosphors

Abstract

Gadolinium Oxide doped with various concentrations of Europium (III), were prepared using the solid-state reaction method. Sample with 1.5 mol% of Europium underwent the XRD characterisation to examine the phases available and to confirm the presence of proper phases in prepared samples. Observed XRD pattern exhibited significantly good resemblance with crystallographic open database card No. 96-101-1289, specifically reported for Gd2O3 with cubic structure and I 21 3 (199) space group. Prepared samples were studied using Photoluminescence (PL) emission spectra. The PL emission expressed various peaks centred at 470, 496, 515, 540, 550, 592 and 616 nm out of which peaks centred at 470, 496, 515, 540 and 550 nm were attributed to 6G11/2, 6G9/2, 6G5/2 6P7/2, peak centred at 592 nm is assigned to 6G7/2 6P7/2 whereas the peak centred at 616 nm may correspond 6G11/2, 6G9/2, 6G5/2 6P3/2 transitions. CIE coordinate was found as (0.40, 0.43) which is under the region described for white light emission. Correlated Colour Temperature (CCT) was estimated as 3853 K and Colour Rendering Index (CRI) was 61. Obtaining CRI in this range enabled us to conclude that emission received is satisfactorily good so far as its application in White LED is concerned.