A novel efficient red-emitting K₇SrY₂B₁₅O₃₀: Eu³⁺ phosphor with non-concentration quenching and robust thermal...

Inhibiting energy migration between Eu³⁺ ions in a fixed host to get higher doping concentration is a permanent topic. Herein, a novel non-concentration quenching red-emitting K₇SrY_2-2xB₁₅O₃₀: xEu³⁺ (0.1 ≤ x ≤ 1.0) phosphor was synthesized via high-temperature sintering method. XRD measurement, Rietveld refinement results, and radius percentage deviation calculation demonstrated the phase purity and the occupation preference of Eu³⁺ ions. With continuously increasing doping Eu³⁺ ions, the absence of concentration quenching could be explained by long distance between two Eu³⁺ (7.012 Å) and the K₇SrEu₂B₁₅O₃₀ could exhibit striking photoluminescence performance with the highest emission wavelength centered at 617 nm. Meanwhile, under the radiation of 393 nm, the high internal quantum efficiency ( ∼ 78.71 %), excellent color purity ( ∼ 88.32 %) and robust thermal stability whose emission intensity at 140 °C could still reach ∼ 97.31 % could guarantee its potential application. When coating BaMgAl₁₀O₁₇: Eu²⁺, (Ba, Sr)₂SiO₄: Eu²⁺, and K₇SrEu₂B₁₅O₃₀ on a near-ultraviolet chip, the bright white light with a low correlated color temperature of 4211 K and CIE color coordinates of (0.3675, 0.3556) could be obtained. Taking the analytic results above, the non-concentration quenching K₇SrY₂B₁₅O₃₀: Eu³⁺ compound has great potential to act as a candidate for red-emitting phosphors in solid-state lighting field.