The development of high-brightness far-red-emitting phosphors with emission wavelength within 650–750 nm is of great significance for indoor plant cultivation light-emitting diode (LED) lighting. Herein, we demonstrate a novel efficient far-red-emitting phosphors CaMg₂La₂W₂O₁₂:Mn⁴⁺ (abbreviated as CMLW:Mn⁴⁺) toward application in plant cultivation LEDs. Interestingly, the CMLW:Mn⁴⁺ phosphors show a broad excitation band in the 250–600 nm spectral range with two peaks at 352 and 479 nm, indicating they could be efficiently excited by near-ultraviolet and blue light. Under 352 nm excitation, the CMLW:Mn⁴⁺ phosphors exhibit an intense far-red emission band in the wavelength range of 650–800 nm peaking at 708 nm, corresponding to the ²E_g → ⁴A_2g transition of Mn⁴⁺ ions. Mn⁴⁺ doping concentration-dependent luminescence properties are studied in detail, and the concentration quenching mechanism is also investigated. Particularly, the internal quantum efficiency of CMLW:Mn⁴⁺ phosphors reaches as high as 44%, and their PL spectra match well with the absorption spectrum of phytochrome P_FR (P_FR stands for far-red-absorbing form of phytochrome). Furthermore, a prototype LED device is fabricated by coating the as-prepared CMLW:0.8%Mn⁴⁺ phosphors on a 460 nm blue LED chip, which produces bright far-red emissions upon 20–300 mA driving currents. This work reveals that the newly discovered far-red-emitting CMLW:Mn⁴⁺ phosphors hold great potential for application in indoor plant cultivation.

开发发射波长在 650-750 nm 范围内的高亮度远红光荧光粉对于室内植物栽培发光二极管（LED）照明具有重要意义。在此，我们展示了一种新型高效远红光荧光粉 CaMg ₂ La ₂ W ₂ O ₁₂ :Mn ⁴⁺（缩写为 CMLW:Mn ⁴⁺）在植物栽培 LED 中的应用。有趣的是，CMLW:Mn ⁴⁺荧光粉在 250-600 nm 光谱范围内显示出宽的激发带，在 352 和 479 nm 处有两个峰，表明它们可以被近紫外光和蓝光有效激发。在 352 nm 激发下，CMLW:Mn ⁴⁺磷光体在 650-800 nm 的波长范围内表现出强烈的远红色发射带，在 708 nm 处达到峰值，对应于Mn ⁴⁺离子的² E _g  →  ⁴ A _2g跃迁。详细研究了Mn ⁴⁺掺杂浓度依赖的发光特性，并研究了浓度猝灭机制。特别是CMLW:Mn ⁴⁺荧光粉的内量子效率高达44%，其PL光谱与光敏色素P _FR (P _FR代表光敏色素的远红吸收形式）。此外，通过在 460 nm 蓝色 LED 芯片上涂覆所制备的 CMLW:0.8%Mn ⁴⁺磷光体来制造原型 LED 器件，该芯片在 20-300 mA 驱动电流下产生明亮的远红光发射。这项工作表明，新发现的远红光 CMLW:Mn ⁴⁺荧光粉在室内植物栽培中具有巨大的应用潜力。