Spectroscopic and photoluminescence characterization of Dy3+ in Sr0.5Ca0.5TiO3 phosphor

The spectroscopic and photoluminescence characteristics of trivalent dysprosium (Dy3+)-doped Sr0.5Ca0.5TiO3 phosphor materials synthesized via solid-state reaction method were studied. The X-ray diffraction profile confirmed the orthorhombic perovskite structure of the prepared samples. Judd-Ofelt analysis was carried out to obtain the intensity parameters and predicted radiative properties of Sr0.5Ca0.5TiO3:2wt%Dy3+. The photoluminescence spectrum of Dy3+-doped Sr0.5Ca0.5TiO3 showed three emission peaks at 481, 574 and 638 nm corresponding to F-4(9/2) -> H-6(15/2), F-4(9/2) -> H-6(13/2) and F-4(9/2) -> H-6(11/2) transitions respectively. The variation of luminescence intensity with different excitation wavelengths and Dy3+ concentrations is discussed. The decay profiles of F-4(9/2) excited levels of Dy3+ ions show bi-exponential behaviour and also a decrease in average lifetime with increase in Dy3+ concentration. Yellow to blue luminescence intensity ratio, CIE chromaticity co-ordinates and correlated color temperature were also calculated for different concentrations of Dy3+-doped Sr0.5Ca0.5TiO3 phosphor at different.ex. Copyright (C) 2015 John Wiley & Sons, Ltd.