Mn⁴⁺-activated (oxy)fluoride-based red phosphors have received extensive attention. In this work, a phase transformation from K₂NbF₇ to K₃HF₂NbOF₅ was successfully achieved by stoichiometric control during coprecipitation process, resulting in a novel red phosphor K₃HF₂NbOF₅:Mn⁴⁺ with narrow-band emission. A systematic study was carried out on its crystal structure and luminescent properties. By introducing O ions into the local coordinated structure, the emission intensity of K₃HF₂NbOF₅:Mn⁴⁺ phosphors is 2.15 times as high as that of K₂NbF₇:Mn⁴⁺ with a photoluminescence internal quantum yield (IQE) of 73.28% and absorption efficiency (AE) of 49.68%, which could be attributed to the layered structure of the oxyfluoride host. High quenching concentration of 8.39 mol% and short decay lifetime of 4.19 ms are realized. Based on K₃HF₂NbOF₅:Mn⁴⁺ and commercial YAG:Ce³⁺, a white light-emitting diode (WLED) for solid state lighting was fabricated, which has low CCT of 3802 K, high Ra of 86.3 and high luminous efficiency (LE) of 126.23 lm/W. Moreover, by employing commercial β-sialon:Eu²⁺ and K₃HF₂NbOF₅:8.39%Mn⁴⁺, another WLED with high LE of 95.78 lm/W and wide color gamut of 108.6% National Television Standard Committee (NTSC) standard for backlight lighting was packaged, indicating a great potential of K₃HF₂NbOF₅:Mn⁴⁺ as a red component in the application of backlight lighting.

Mn ⁴⁺活化的（氧）氟化物基红色磷光体受到广泛关注。在这项工作中，通过共沉淀过程中的化学计量控制成功地实现了从 K ₂ NbF ₇到 K ₃ HF ₂ NbOF ₅的相变，从而产生了一种具有窄带发射的新型红色荧光粉 K ₃ HF ₂ NbOF ₅ :Mn ⁴⁺ . 对其晶体结构和发光特性进行了系统研究。通过将 O 离子引入局部配位结构，K ₃ HF ₂ NbOF ₅ :Mn的发射强度⁴⁺磷光体为2.15倍那样高K个₂ NBF ₇：锰⁴⁺具有73.28％的光致发光的内部量子效率（IQE）和吸收效率的49.68％（AE），这可以归因于的层状结构氟氧化物宿主。实现了 8.39 mol% 的高猝灭浓度和 4.19 ms 的短衰减寿命。基于K ₃ HF ₂ NbOF ₅ :Mn ⁴⁺和商用YAG:Ce ³⁺，制备了一种用于固态照明的白光发光二极管（WLED），其具有3802 K的低CCT、86.3的高Ra和高发光效率 (LE) 为 126.23 lm/W。此外，通过使用商用 β-sialon:Eu ²⁺和 K ₃ HF ₂ NbOF ₅ :8.39%Mn ⁴⁺，封装了另一种具有 95.78 lm/W 高 LE 和 108.6% 国家电视标准委员会 (NTSC) 背光照明标准的宽色域的 WLED，显示出巨大的潜力K ₃ HF ₂ NbOF ₅ :Mn ⁴⁺作为背光照明应用中的红色成分。