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.

High-performance and thermally stable phosphors play an important role in high-quality white light-emitting diode (pc-WLED) lighting. In this work, we proposed a cation substitution strategy to improve the luminescence performance of blue-emitting Bi3+-doped Ca4ZrGe3O12 (abbreviated as CZGO) phosphor. As expected, the introduction of Sr2+ and Si4+ can improve photoluminescence intensity and thermal stability. The photoluminescence intensity can be increased by 6.7 times. The internal quantum efficiency (IQE) can achieve 88.1%. Based on Rietveld refinement results, the corresponding enhancement mechanism is ascribed to the local lattice modification and the improved structure rigidity. In addition, controllable color tuning from blue to red light is successfully realized through designing Bi3+ → Eu3+ energy transfer. The energy transfer efficiency (ηT) is 0.55 in CZGO:2% Bi3+, 15% Eu3+ phosphor. The energy transfer mechanism is discussed in detail. The prototype pc-WLEDs with blue/red dual-emitting CZGO:2% Bi3+, 10% Eu3+ possess a high color rendering index (CRI = 90.8) and low correlated color temperature (CCT = 4372 K). The above investigations indicate that CZGO:Bi3+ and CZGO:Bi3+, Eu3+ are promising blue-to-red tunable phosphor candidates for pc-WLED applications.

Phosphor-converted white light-emitting diodes (pc-WLEDs) as one of the most famous solid-state lighting sources has extensively penetrated into our daily lives due to the high luminescence efficiency, low energy consumption, durability and eco-friendly features.How to further improve the luminous efficiency of trichromatic phosphor materials is the key and difficult point to achieve high quality white LED lighting, and has being always the research hotspot in the field of luminescent materials. Among various inorganic phosphor materials, green emitting phosphors commonly demonstrate the main contribution to the luminescence efficiency of WLEDs compared with another employed luminescence materials such as blue and red phosphor materials. Therefore, the development of highly efficient green phosphor materials is extremely necessary.In this work, we designed Ce 3+ , Eu 2+ codoping and P 5+ ↔Si 4+ cation substitution in the presentative Ba 3 Si 6 O 12 N 2 :Eu 2+ green phosphor to realize an enhancement of luminescence efficiency and thermal stability. Rietveld refinement results confirmed the formation of pure trigonal phase (P-3) of Ba 3 Si 6 O 12 N 2 and the successful doping of Ce 3+ , Eu 2+ , P 5+ ions.Ce 3+ and Eu 2+ ions randomly occupy two Ba crystallographic sites (Ba1 and Ba2). Ce 3+ and

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