Synergetic manipulation of components and multiple activator sites towards full-spectrum lighting in Eu2+-doped whitlockite phosphors for high color-rendering WLED

https://doi.org/10.1016/j.jlumin.2024.120795

Tuning the components and multiple activator sites possesses profound significances on the regulation for corresponding luminescent properties of target phosphors. However, it is still challenging to realize full-visible emission via single activator in a single phase owing to the matrix diversity and uncertainty for multi-site occupation. Herein, we developed a family of whitlockite-type solid-solution phosphors Ca₈MgGa_1-yLa_y(PO₄)₇: Eu²⁺(y = 0–1) via inducing the La³⁺ ions into Ca₈MgGa(PO₄)₇:Eu²⁺. The local environments of Eu²⁺ ions and corresponding tunable photoluminescent properties, decay times and thermal stability are revealed systematically in detail. Specially, the excitation and emission spectra of Ca₈MgGa_1-yLa_y(PO₄)₇: Eu²⁺ are broadened gradually, finally towards a full-visible emission with 152 nm bandwidth spectrum for the phosphor Ca₈MgLa(PO₄)₇: Eu²⁺. WLED with a high color rendering index (CRI = 95) and low color temperature (CCT = 3764 K) was fabricated based on the full-visible emission Ca₈MgGa_0.2La_0.8(PO₄)₇: 0.08Eu²⁺ phosphors under a 365 nm chip, indicating the prominent potentials for high-color-rendering WLEDs. These results in current work provide new ideas for synergetic manipulation of components and multiple activator sites towards a full-visible emission in single-phase applied for white lighting.