Synthesis and luminescence characterization of Sr0.5Ca0.5TiO3:Sm3+ phosphor

• Successfully synthesized Sm3+ doped Sr0.5Ca0.5TiO3 phosphors via solid state reaction method.
• JO intensity parameters and radiative properties were calculated.
• Non-radiative energy transfer rate, quantum efficiency and gain coefficient were evaluated from the decay analysis.
• The CIE color co-ordinates of the prepared phosphor samples vary from greenish yellow to yellowish orange.

The spectroscopic properties of trivalent samarium doped Sr0.5Ca0.5TiO3 perovskite phosphor material (Sr0.5Ca0.5TiO3:xSm3+, x = 0.05, 0.1, 0.5, 1, 1.5) synthesized by the solid state method have been studied. The X-Ray Diffraction profile confirms the orthorhombic perovskite Sr0.5Ca0.5TiO3 structure of the prepared samples. The SEM study reveals the surface morphology. The Judd–Ofelt intensity parameters were calculated for 0.5 wt% Sm3+ doped Sr0.5Ca0.5TiO3. Transition probabilities, branching ratios and radiative lifetime were evaluated by using Judd–Ofelt analysis. The emission spectra under 405 nm excitation shows five emission peaks at 564 nm, 599 nm, 645 nm, 707 nm and 776 nm corresponding to the transitions 4G5/2 → 6Hj (j = 5/2, 7/2, 9/2, 11/2 and 13/2) respectively. The higher values of branching ratio and stimulated emission cross-section for 4G5/2 → 6H7/2 transition of Sr0.5Ca0.5TiO3:0.5 wt% Sm3+ shows its suitability in the field of visible lasers and optical fiber amplifiers. The experimental lifetimes of Sm3+ doped samples were estimated using the decay curves corresponding to 4G5/2 → 6H7/2 transition upon 405 nm excitation. Concentration dependence on emission intensity and experimental lifetime were also studied. From the CIE diagram we can see that as the concentration of Sm3+ ions increases from 0.05 wt% to 1.5 wt% the CIE color co-ordinates changes from greenish yellow to yellowish orange.

Figure optionsDownload as PowerPoint slide