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Thermal quenching (TQ) of phosphor is one of the biggest challenges to develop high‐quality white light‐emitting diodes (w‐LEDs). Herein, an anti‐thermal‐quenching (anti‐TQ) property in cyan‐emitting Ba2ZnGe2O7:Bi3+ phosphor is reported. At 150 °C, its emission intensity increases to 114% of the original intensity at 25 °C. Especially, the integrated emission intensity reaches 138%, 148%, and 134% at 150, 200, and 250 °C, respectively, by artificially creating zinc and oxygen vacancy defect. The anti‐TQ phenomenon is mainly attributed to high structure rigidity and strong ability to compensate emission loss during thermal generation process. Thermal‐induced emission compensation mainly stems from self‐oxidization behavior of Bi2+ in zinc vacancy and the presence of oxygen vacancy defect. Oxygen vacancy is induced by native zinc vacancy and charge imbalance between Bi3+ and Ba2+ ions. The strategy to create oxygen vacancy defect and design self‐oxidization process of Bi opens a new insight to exploit anti‐TQ phosphors for high‐quality w‐LEDs applications. [ABSTRACT FROM AUTHOR]

A novel La2Mg1.14Zr0.86O6:Bi3+ double perovskite phosphor with excitation-induced blue/green photoluminescence tuning is reported. By designing Bi3+ → Eu3+ energy transfer, single-composition white light with wide-scale adjustable corrected color temperatures (CCTs) is successfully achieved. This work initiates a new insight to explore phosphors with excitation-induced photoluminescence tuning and wide CCT control for future intelligent LED lighting. [ABSTRACT FROM AUTHOR]

Highly efficient green/yellowish‐orange phosphors with low thermal quenching behavior are urgently required to improve the luminescence efficiency, color stability, and color rendering of phosphor‐converted white light emitting diodes (w‐LEDs). Herein, a novel green Cs2BaP2O7:0.01Eu2+ phosphor with high luminescence efficiency (82.7%) and thermal quenching behavior (92.5% at 423 K) is reported. Besides, a further luminescence improvement in the quantum yield (98.9%) and thermal quenching resistance (120% at 448 K) is successfully achieved in green/yellowish‐orange color‐tunable Cs2MP2O7:0.01Eu2+ (M = Ba, Sr, and Ca) phosphors. Surprisingly, these green/yellowish‐orange Cs2MP2O7:0.01Eu2+ (M = Ba, Sr, and Ca) phosphors even have a prior advantage over the commercial green β‐SiAlON:Eu2+ and yellow YAG:Ce3+ phosphors. The corresponding spectral adjustment and thermal stability mechanisms are revealed, related to the optimization of local lattice symmetry. The prototype w‐LEDs exhibit warm white light with CIE color coordinate at (0.337, 0.322). The color rendering index, corrected color temperature, and luminescence efficiency can reach 92.6, 4044 K, and 152.56 lm W−1, respectively. In general, the as‐reported green/yellowish‐orange Eu2+‐doped pyrophosphate phosphors are promising candidates in the future high‐quality w‐LEDs applications. The proposal of local lattice symmetry modulation can provide a new approach to exploit novel phosphors with excellent thermal quenching resistance. [ABSTRACT FROM AUTHOR]

To optimize luminescence properties of oxonitridosilicate phosphors are extremely necessary for improving lighting quality of white light-emitting diodes (WLEDs). Herein, we designed Ce3+, Eu2+ codoping and P5+↔Si4+ substitution in the presentative Ba 3 Si 6 O 12 N 2 :Eu2+ green phosphor to realize an enhancement of luminescence efficiency and thermal stability. Rietveld refinement results of Ce3+, Eu2+, P5+-doped Ba 3 Si 6 O 12 N 2 (BSON) confirmed the formation of pure trigonal phase (P -3) of Ba 3 Si 6 O 12 N 2 and the successful doping of Ce3+, Eu2+, P5+ ions. Ce3+ and Eu2+ ions randomly occupy two Ba crystallographic sites. Interestingly, a near unity energy transfer (ET, ~100%) from Ce3+ ions to Eu2+ ions is observed. Meanwhile, the doping of P5+ ions into BSON also helps improving the luminescence efficiency and thermal stability, which should be attributed to the charge compensation and the relax of lattice strain. In addition, the white light emitting diodes (WLEDs) fabricated by employing P5+-doped BSON: Eu2+ present a better electroluminescence performance than BSON: Eu2+. This study could serve as a guide in developing optimized oxonitridosilicates phosphors with improved luminescence performances based on complete energy transfer and lattice variations in local coordination environments through cation substitutions, and the as-prepared Ce3+/P5+-codoped Ba 3 Si 6 O 12 N 2 :Eu2+ could be an excellent green-emitting phosphor for UV-to-Visible LED chips pumped WLEDs. • A near unity energy transfer from Ce3+ to Eu2+ was realized in Ba 3 Si 6 O 12 N 2 host. • Based on Ce3+.→Eu2+ ET, the luminescence intensity was enhanced to 2.5 times. • An emission tuning from blue (0.173, 0.148) to green (0.259, 0.571) was realized. • P5+ doping into BSON helps to improve luminous efficiency and thermal stability. • The WLEDs fabricated with BSON:Eu2+,P5+ present a better luminescence performance. [ABSTRACT FROM AUTHOR]