Mn4+ activated dodec-fluoride red phosphor Na3Li3In2F12:Mn4+ with excellent waterproof stability for WLEDs

Optical enhancement of highly efficient organic–inorganic oxyfluoride red phosphors via the cation co-doping strategy

“…The results indicate that the new [N(CH 3 ) 4 ] 3 MoO 3 F 3 matrix can meet the high requirements of the crystal field environment for Mn 4+ doping. 23–37 For details of the calculation process, see Fig. S2 and Table S2†.…”

“…Fig. 1f shows the fluorescence lifetime decay curves ( λ ex = 470 nm, λ em = 632 nm) of [N(CH 3 ) 4 ] 3 MoO 3 F 3 : x Mn 4+ ( x = 2%, 4%, 6%, 8% and 10%) phosphors, which can be fitted with a single exponential function (eqn (5)): 27,43 I ( t ) = I 0 exp (− t / τ ) + A where I 0 and I ( t ) denote the initial fluorescence intensity and emission intensity at moment t of the as-prepared samples, τ is the fluorescence decay time, and A represents a constant. When the concentration of Mn 4+ increased from 2% to 10%, the fluorescence lifetimes of the samples were 3.90 ms, 3.76 ms, 3.49 ms, 2.89 ms and 2.88 ms, respectively.…”

Theoretical calculations and photoluminescence properties of Sr4Al14O25:Mn4+ red phosphors doped with Li+

“…Compared with commercial red fluorescein phosphors K 2 SiF 6 :Mn 4+ , the PL strength of Na 3 Li 3 In 2 F 12 :Mn 4+ fluorescein phosphors remained at the initial 80% when immersed in water for 360 minutes. Unfortunately, the thermal stability of the phosphors is insufficient, being only 26% of their initial strength at 423 K. 30 In summary, Mn 4+ fluoride red phosphors exhibit poor stability, which limits the application of red phosphors. Correspondingly, the chemical stability of oxide red phosphors (Ba 3 WO 6 :Mn 4+ , Ba 2 LaTaO 6 :Mn 4+ , Sr 2 ScSbO 6 :Mn 4+ , and Sr 4 Al 14 O 25 :Mn 4+ ) is better than that of fluoride red phosphors.…”

Synthesis and study of luminescence properties of a deep red–emitting phosphor K2LiAlF6:Mn4+ for plant cultivation

“…Many studies have discovered that the best hosts for Mn 4+ doping with strong luminous characteristics are fluorides and oxides [23]. Mn 4+ ‐activated fluoride red phosphor has attracted much interest in recent years because of its high UV and blue‐light absorption, red light between 600 and 680 nm, gentle manufacturing process and inexpensiveness [24]. It is widely acknowledged that Mn 4+ ions exhibit a broad and powerful absorption in the wavelength range of 200–550 nm due to the 4 A 2g to ( 4 T 1g , 2 T 2g and 4 T 2g ) transitions of Mn 4+ ions and emit off‐red to near‐infrared light ranging from 620 to 780 nm due to the 2 E g → 4 A 2g transition of Mn 4+ ions.…”