Optical studies and estimation of kinetic parameters for dysprosium activated yttrium oxide phosphors

Dysprosium doped Y2O3 phosphors have been prepared via facile solid-state reaction (SSR) method. Cubic structure of Y2O3: Dy3+ phosphors were obtained through X-ray diffraction (XRD). FEGSEM analysis shows agglomerated irregular structures with uniform grain connectivity. The functional group analysis is done by Fourier transforms infrared spectroscopy (FTIR). The photoluminescence (PL) analysis reveals that these phosphor exhibits instance blue emission at 484 nm, 574 nm, 585 nm and 614 nm due to transitions 4F9/2 to 6H15/2, 4F9/2 to 6H13/2 and 4F9/2 to 6H11/2 respectively, under 570 nm excitation wavelength. The CIE coordinates, CCT and afterglow analysis were also done. Emission and cross relaxation mechanisms were explained by energy levels diagram. Thermoluminescence (TL) spectra of show intense peaks at 640K for gamma irradiated phosphors. The TL spectra were deconvoluted by computerized glow curve deconvolution (CGCD) technique. Kinetic parameters were calculated with the help of Chen's peak shape method. The recorded TL spectra show the linear behaviour with respect to variation of gamma exposures time with the activation energy varying from 15.523 × 10−1 eV to 21.906 × 10−1 eV.