Optical properties of Ca12Al14O33: RE (RE = Dy3+, Sm3+, Tb3+) phosphor prepared by combustion method

The Ca12Al14O33: RE (RE = Dy3+, Sm3+, Tb3+) phosphor was synthesized by a simple combustion technique. The X-ray diffraction study reveals that phosphor was synthesized successfully. Rietveld refinement parameter obtained using the Full-Proof software. The photoluminescence characteristics were studied for various concentrations (x = 0.5, 1.0, and 1.5 mol%) of Dy3+, Sm3+, and Tb3+, where the concentration quenching occurs for 1.0 mol%. The major excitation peak was observed for the Ca12Al14O33: Dy3+ phosphor at 349 nm which is attributed due to F-6(7/2) -> P-6(7/2) while the peak obtained at 388 nm is due to F-6(7/2) -> I-4(13/2). In comparison, Ca12Al14O33: Sm3+ phosphor showed the two excitation peaks at 345 nm and 377 nm noted due to H-6(5/2)-> H-4(9/2) and H-6(5/2) -> P-6(7/2), and Ca12Al14O33: Tb3+ phosphor excitation peaks obtained at 351 nm are caused by F-7(6) -> L-5(9) transition whereas 378 nm are caused by F-7(6) -> D-5(3). The two emission peaks were noticed for Dy3+ ions at 474 nm (Blue) and 573 nm (Orange) regions due to the F-4(9/2) -> F-6(15/2) and F-4(9/2) -> F-6(13/2). Two intense emission bands obtained around 566 (Orange) and 603 nm (Red) due to (4)G(5/2) -> H-6(5/2) and (4)G(5/2) -> H-6(7/2) transition of Sm3+ ions, and the emission peaks observed for Tb3+ ion at 489 nm (Blue) and dominant peak at 545 (Green) nm are ascribed to D-5(4) -> F-5(6) and D-5(4) -> F-5(5) transitions. SEM-EDX study determines the particle size and elemental constitution of prepared phosphor. The band gap is obtained using UV-visible spectroscopy. CIE color chromaticity coordinate was calculated which shifted in Blue, Red, and Green regions for respective rare earth ions (RE = Dy3+, Sm3+, Tb3+). The photoluminescence property of the Ca12Al14O33: RE (RE = Dy3+, Sm3+, Tb3+) phosphor reveals that the given phosphor has good caliber for solid-state and green light application