Mechanochemical preparation of Mn4+-activated K3MoO3F3 phosphors with short fluorescence lifetime

Mn 4+ -activated oxy-fluoride red phosphors have garnered increasing attention. However, the majority of oxy-fluoride phosphors necessitate the utilization of HF during the synthesis process, which brings a huge threat to the human health and the environment. In this work, K 3 MoO 3 F 3 :Mn 4+ red phosphors were prepared by a mechanical grinding method. The process is environmentally friendly, streamlined, and minimally detrimental to the environment. This phosphor shows narrow emission around ∼631 nm excited by 470 nm blue light with high color purity of 99.60 %. Satisfactorily, in Mn 4+ -doped oxy-fluoride molybdate phosphors, the K 3 MoO 3 F 3 :3 % Mn 4+ red phosphor has a very short fluorescence lifetime (1.87 ms) and good thermal stability, which still maintains 65.84 % of its original intensity at 423 K. The fabricated warm WLED device has a low correlated color temperature (4085 K) and a high color rendering index (Ra = 85). The results suggest that K 3 MoO 3 F 3 :Mn 4+ possesses significant potential for applications in white LEDs.