Synthesis and Characterization of Sr0.5Ca0.5Tio3: x Eu3+ Reddish- orange

Phosphors

Sr 0.5 Ca 0.5 TiO 3 : x Eu 3+ phosphor samples were synthesized via solid state reaction technique. The orthorhombic perovskite structure of the prepared phosphors was confirmed using XRD measurements. The microstructure of the phosphor samples was observed from the SEM images. The FTIR spectra show the chemical bonding in the prepared Sr 0.5 Ca 0.5 TiO 3 :x Eu 3+ phosphor samples. The band gap energy of the phosphors were calculated from the absorption spectra. The emission spectra of Sr 0.5 Ca 0.5 TiO 3 : 2 Eu 3+ phosphor samples at different excitation wavelengths were also studied and the maximum emission intensity was observed for an excitation wavelength of 463 nm.

Asymmetric ratio of the samples indicates that the majority of Eu 3+ ions occupy sites with lower symmetry or at non-inversion symmetry sites. As the concentration of Eu 3+ increases the emission intensity also increases shows the absence of concentration quenching till 2wt% of Eu 3+ ions. As the doping concentration of Eu 3+ increases from 0.05 wt% to 2 wt% the CIE color coordinates change from orange to reddish-orange. The correlated color temperature of the prepared phosphor samples was calculated from the chromaticity coordinates and the values obtained are in the warm CCT region with reasonable color purity. So we can conclude that Sr 0.5 Ca 0.5 TiO 3 : 2 Eu 3+ phosphor sample, which has the highest emission intensity and color purity, can be used for the WLED applications.