New Deep-Blue-Emitting Ce-Doped A_4–mB_nC_19+2mX_29+m (A = Sr, La; B = Li; C = Si, Al; X = O, N; 0 ≤ m ≤ 1; 0 ≤ n ≤ 1) Phosphors for High-Color-Rendering Warm White Light-Emitting Diodes

Abstract

A new sialon Eu 3.60 LiSi 13.78 Al 6.03 O 6.82 N 22.59 has been discovered via the single-particle diagnosis approach. Its crystal structure (space group P3m1) was solved and refined from single crystal X-ray diffraction data. It has the interesting feature of two types of disorder at the Eu2 site: positional disorder (Eu2a/Eu2b) and substitutional disorder with (Si/Al) 2 (O/N)). The structure is generalized to the formula A 4-m B n C

Ca[B8O11(OH)4] : Eu2+ – A Highly Efficient Deep Blue‐Emitting Phosphor Prepared by Low‐Temperature Self‐reduction

“…Driven at a current of 20 mA, the emission spectrum of WLED can cover the entire visible light region, as shown in Figure 8a. The inset in Figure 8a shows the corresponding photograph of the lightened WLED, which emits bright white light, whose LE is13.9 lm/W, CRI is 89.4, and CCT is 5825 K. The CRI and luminous efficiency are higher than those of the reported materials, such as 0.2 β ‐Ca 3 (PO 4 ) 2 ‐0.8Ca 9 La(PO 4 ) 7 :0.01Eu 2+ ,0.20Mn 2+ (CRI=86.9, LE=11.7 lm/W), [11] but lower than those of the reported materials, such as Sr 3.61 LiSi1 4.27 Al 5.61 O 6.19 N 23.25 :0.05Ce (CRI=96, LE=17.8 lm/W) [78] . The CIE color coordinate of WLED is (0.326, 0.328), as shown in Figure 8b.…”

“…The PLQY of CBH : 2 %Eu 2+ is higher than those of the perovskite type of CsPbBr x Cl 3−x (PLQY=89 %), [61] the UCr 4 C 4 type of RbNa 3 (Li 3 SiO 4 ) 4 : Eu 2+ (PLQY=53 %), [15] commercial phosphor of BaMgAl 10 O 17 : Eu 2+ (PLQY=92.4 %) [14] and other aluminate of BaAl 12 O 19 : Eu 2+ (PLQY=90 %), [59] borates of Ba 3 Y 2 B 6 O 15 :Ce 3+ (PLQY=84 %), [62] BaAlBO 3 F 2 : Eu 2+ (PLQY=76 %), [63] Ba 2 (Y 1−x Lu x ) 5 B 5 O 17 :Ce 3+ (x=0∼1) (PLQY=90 %), [64] and phosphate of Sr 4.99 (PO 4 ) 3 Cl:0.01Eu 2+ (PLQY=80.5 %) [16] . The external quantum efficiency (EQE) of CBH : Eu 2+ is measured to be 31.1 %, which is higher than those of the recently reported blue phosphor of (Na 2−2x Eu x )MgPO 4 F (EQE=18.1 %), [65] Na 0.58(4) K 0.42(4) Li 3 SiO 4 : Eu 2+ (EQE=30.0 %), [66] and KMg 4 (PO 4 ) 3 : Eu 2+ (EQE=18.6 %), [67] but lower than those of K 2 YZr(PO 4 ) 3 : Eu 2+ (EQE=40 %), [68] and Sr 3.61(1−x) Eu 3.61 xLiSi 14.27 Al 5.61 O 6.19 N 23.25 (EQE=37 %), [69] and commercial BAM : Eu 2+ phosphor (EQE=37 %) [67] …”

Development of sialon phosphors and their applications to solid-state lighting

“…Extra-high CRIs were achieved by adding 36) Alternatively, the ultra-high CRI can be obtained by pumping the phosphor mixtures with a nUV LED. In this case, blue-emitting phosphors, such as JEM: Ce 3+ , 53) AlN:Eu 2+ , 54) La 3 Si 6.5 Al 1.5 N 9.5 O 5.5 :Ce 3+ , 55) and Sr 3.61 LiSi 14.27 Al 5.61 O 6.19 N 23.25 :Ce 3+ , 56) were developed. The CRIs of the nUV-pumped wLEDs are usually higher than 95, together with R9 > 90 and R12 > 90.…”

Single White-Emitting Phosphor (Ba,Sr,Ce)4–mLi(Si,Al)19+2m(O,N)29+m for White LEDs

“…Lanthanide-doped silicon aluminum oxy-nitride (sialon)based phosphors are an important class of phosphors for white LED applications, as several sialon phosphors have shown to be very energy-efficient with high thermal and chemical stability. 18 Due to the structural versatility of sialons, sialon phosphors have been obtained by doping with Eu 2+ or Ce 3+ that emit different types of light, varying from blue to green, 21 This sialon phase crystallizes in the P3m1 space group, which has an interesting structural feature that a part of the A atoms are located on a small oxygen site. When doped with Ce, S r 3 .…”