Abstract
Based on crystal site engineering, a series of inorganic Ba9Lu2Si6O24: Eu2+ (BLSO: Eu2+) and Ba9Lu2Si6O24:Eu2+, Mn2+ phosphors were synthesized. These phosphors exhibit broad emission throughout the whole visible spectrum range. More specifically, a systematic cation substitution favored efficient energy transfer. Hence, the produced Ba9Lu2−zSczSi6O24: 0.2Eu2+, 0.4Mn2+ (BLSSO: 0.2Eu2+, 0.4Mn4+) were effective single-phase white-light-emitting phosphors. Particularly, Ba9Lu2Si6O24: Eu2+ phosphors emit a broadband blue emission peaking at 462 nm with a long tail. The results of the emission spectrum's Gaussian fitting (and deconvolution), low-temperature photoluminescence, and decay time observations point to the existence of many luminescence centers in the host lattice of BLSO. Partial cation substitution favors the occupation of Eu2+ ions in other available crystallographic sites, i.e., Ba(2) and Ba(3), resulting in the emission spectrum broadening in the green spectral region. The energy transfer from the doped Eu2+ to the co-doped Mn2+ ions broadens the emission in the red spectral region (618 nm). Accordingly, the broadband emission covers the entire visible spectral region. Furthermore, the make-up of these phosphors provides a powerful method for obtaining continuous tuning throughout the whole visible spectrum. The above features, in conjunction with the color coordinates and the remarkable thermal stability, qualify the optimized Ba9Lu2−zSczSi6O24: 0.2Eu2+, 0.4Mn2+ phosphor for potential use in single-phase white-light-emitting phosphors.
•Single phase Ba9Lu2−zSczSi6O24:0.2Eu2+, 0.4Mn2+ white light emitting phosphors is synthesized.•Ba9Lu2−zSczSi6O24:0.2Eu2+, 0.4Mn2+ emit dual emission peaking at 500 nm and 618 nm.•The photoluminescence excitation is matching well with UV emitting chip.•Both excitation and emission can be tuned with systematic cation substitution and energy transfer.