Preparation, structural and photoluminescence characteristics of novel red emitting Mg7Ga2GeO12:Mn4+ phosphor

Synthesis, Crystal Structure, and Photoluminescence Characteristics of High-Efficiency Deep-Red Emitting Ba2GdTaO6:Mn4+ Phosphors

“…Under 358 nm excitation, the IQE of the BGT:0.6%Mn 4+ sample was measured using an integrating sphere, as shown in Figure a, which could be calculated by the following equation where η is the IQE; L S is the emission spectrum of the sample; and E S and E R are the spectra of the excitation light with the BGT:0.6%Mn 4+ sample and only with BaSO 4 reference, respectively. Thus, the calculated IQE was 44%, which was higher than that of the recently reported Mn 4+ -activated red-emitting phosphors, such as Mg 7 Ga 2 GeO 12 :Mn 4+ (IQE: 28.13%), La­(MgTi) 1/2 O 3 :Mn 4+ (IQE: 27.2%), and SrLaScO 4 :Mn 4+ (IQE: 12.2%). − Furthermore, we also measured the IQEs for other samples of BGT: x Mn 4+ phosphors using the same integrating sphere method. As shown in Figure b, the IQE values of BGT: x Mn 4+ phosphors ( x = 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2 mol %) under 358 nm excitation were calculated to be about 62, 52, 44, 41, 32, and 24%, respectively.…”

“…Thus, the calculated IQE was 44%, which was higher than that of the recently reported Mn 4+ -activated red-emitting phosphors, such as Mg 7 Ga 2 GeO 12 :Mn 4+ (IQE: 28.13%), La(MgTi) 1/2 O 3 :Mn 4+ (IQE: 27.2%), and SrLaScO 4 :Mn 4+ (IQE: 12.2%). 62−64 Furthermore, we also measured the IQEs for other samples of BGT: x Mn 4+ phosphors using the same integrating sphere method. As shown in Figure 7b, the IQE values of BGT: x Mn 4+ phosphors ( x = 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2 mol %) under 358 nm excitation were calculated to be about 62, 52, 44, 41, 32, and 24%, respectively.…”

Thermally stable La2LiSbO6:Mn4+,Mg2+far-red emitting phosphors with over 90% internal quantum efficiency for plant growth LEDs

“…The IQEs of LLS:0.3%Mn 4+ and LLS:0.3%Mn 4+ ,1.6%Mg 2+ (see Fig. 4(c)) were measured to be 61% and 92%, respectively, which was higher than that of K 2 [58][59][60] The decay lifetime of the LLS:0.3%Mn 4+ ,1.6%Mg 2+ phosphors was longer than that of LLS:0.3%Mn 4+ counterpart (see Fig. 4(d)).…”

“…4(c) ) were measured to be 61% and 92%, respectively, which was higher than that of K 2 NaAlF 6 :Mn 4+ (IQE = 58.4%), Ba 2 TiGe 2 O 8 :Mn 4+ (IQE = 35.6%), and Mg 7 Ga 2 GeO 12 :Mn 4+ (IQE = 28.13%). 58–60 The decay lifetime of the LLS:0.3%Mn 4+ ,1.6%Mg 2+ phosphors was longer than that of LLS:0.3%Mn 4+ counterpart (see Fig. 4(d) ).…”

Synthesis, structure, and luminescence characteristics of far-red emitting Mn4+-activated LaScO3perovskite phosphors for plant growth

“…Mn 4+ ions can replace specic cationic sites of the specic host, where cationic sites have a coordination number (CN) of six, such as Nb 5+ , Zr 4+ , Ti 4+ , Te 6+ , and W 6+ ions. 39,40,[45][46][47][48] Considering the cationic radius and the coordination environment of Mn 4+ (r ¼ 0.535Å, CN ¼ 6) and Sc 3+ (r ¼ 0.745Å, CN ¼ 6), 43,49,50 the Mn 4+ ions could replace the Sc 3+ sites in the LaScO 3 host.…”