Structural and color tunable properties in Sm3+/Eu3+-doped Ca3Bi(PO4)3 phosphor for solar cell and w-LED applications

Crystalline eulytite-type Ca 3 Bi(PO 4 ) 3 (CBP) phosphors activated with Sm 3+ and combination of Sm 3+ & Eu 3+ ions have been prepared by co-precipitation technique. Phase and crystal structure have been recognized using X-ray diffraction analysis and Rietveld refinement. The Sm 3+ -doped CBP phosphor exhibits three emission peaks at 562, 598, and 644 nm under 400 nm excitation and the highest emission intensity has been observed for 5.0 mol% Sm 3+ -doped CBP phosphor. The co-doping of Sm 3+ and Eu 3+ ions in CBP phosphor has expanded the excitation as well as emission spectra. The energy transfer (ET) between Sm 3+ sensitizer ions to Eu 3+ activator ions in CBP phosphor has been studied based on the photoluminescence (PL) and decay curves using Dexter ET formula and Reisfeld's theory. The PL quantum yield was obtained as high as 86.65%, indicating a potential red constituent in photonic devices. The CBP:Sm 3+ /Eu 3+ emission intensity was persisting to 81.27% at 150 °C in comparison to the emission intensity at room temperature, confirming the excellent thermal stability. Moreover, the color coordinates and decay curves have enhanced the suitability of CBP:Sm 3+ , Eu 3+ for accomplishing spectral conversion in solar cells, pc-w-LEDs, and other photonic devices.