Photoluminescence decay curve analysis of some rare earth doped CeO 2 phosphors

CeO2:M (Eu3+, Er3+ and Dy3+) phosphors were synthesized by modified solid-state reaction technique at variable concentrations of Eu3+, Er3+ and Dy3+. This technique is suitable for large-scale production and it is less time-consuming. The prepared samples were characterized by X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), and Photoluminescence (PL) decay curve analysis. XRD patterns of the prepared samples confirm the cubic fluorite crystal structure of all phosphors. Crystallite size was calculated by using well known Scherer’s formula. SEM images express good surface morphology with nanoflower like shape. Comparative studies of photoluminescence decay curves of CeO2:M (Eu3+, Er3+ and Dy3+) with different concentrations of dopant have been done. Decay constants for all prepared phosphors were calculated by curve fitting technique. Samples were excited under UV radiation for few nanoseconds at room temperature. The PL decay curves were measured for 5D0→7F1 transition of CeO2:Eu3+,4S3/2→4I15/2 transition of CeO2:Er3+ and 4F9/2→6H13/2 transition of CeO2:Dy3+ phosphors. Decay curve for CeO2:Eu3+ (1.5 mol%) phosphor shows optimum concentration with higher intensity of photoluminescence signals and comparatively higher decay constants.