Investigation into the surface chemical analysis and luminescent properties of La7O6(BO3)(PO4)2:Dy phosphor

The exploitation of high-quality borophosphate-based phosphor products is currently garnering a significant research focus in solid-state light source. The interest is due to its low-cost and environment-friendly synthesis. In this paper, a new La7O6(BO3)(PO4)(2) (LBP):Dy phosphor was developed via sintering at 1673 K for 3 h under an air atmosphere. Structural characterization indicates that all of the prepared products are the monoclinic phases with the space group P2(1)/n. A comparison of the surface chemical states of the elemental compositions for the LBP host versus optimal LBP:13%Dy product was conducted via X-ray photoelectron spectroscopy. Optical characterization shows that the Dy-doped products exhibited visible light emissions of Dy3+ from F-4(9/2) to H-6(15/2), H-6(132), and H-6(15/2) upon exposure to 348 nm near-ultra violet irradiation. The dominant emission (yellow, 576 nm) belongs to the F-4(9/2) -> H-6(13/2) transition. The best Dy content for doping was 13 mol%, and content quenching occurred due to dipole - dipole interaction. The measured decay lifetime and calculated chromatic properties together manifest that the optimal LBP:13%Dy phosphor shows potential as a yellow ingredient in solid-state lighting.