Broadband near-infrared luminescence in a cubic pyrophosphate Al_0.5Ta_0.5P₂O₇:Cr³⁺ phosphor for multi-functional applications

Abstract

Near-infrared phosphor-converted light-emitting diode (NIR pc-LED) is considered as a next-generation of NIR light source for spectroscopy. However, it is still a challenge to develop an inexpensive broadband NIR phosphor...

Efficient and Tunable Near-Infrared Luminescence in Cubic Phosphate K2AlTi(PO4)3:Cr3+ for Spectroscopy Applications

“…There’s room for PLQY to be further promoted since the SEM image of the sample suggests that the particles are in irregular shape with average size of only ∼3 μm (Figure S4). The PLQY value of this material is much higher than some previously reported materials with similar emission peak wavelengths as presented in Figure d, making it attractive to be applied in NIR pc-LEDs. ,,− …”

“…Additionally, the thermal stability is another important parameter for practical application of the phosphor. The raw 23 Y 0.57 La 0.72 Sc 2.71 (BO 3 ) 4 :Cr 3+ (B), 46 Ga 4 GeO 8 :Cr 3+ (C), 42 ScF 3 :Cr 3+ (D), 45 LiInP 2 O 7 :Cr 3+ (E), 47 and NaScSi 2 O 6 :Cr 3+ (F). 44 (e) Decay curves of K 2 Al 1−x Ti(PO 4 ) 3 :xCr 3+ (x = 0, 0.02, 0.04, 0.06, 0.08, 0.1, and 0.12) samples.…”

“…Therefore, an excellent efficiency can be expected in Cr 3+ -activated octahedral Al 3+ -containing materials from the insight into crystal chemistry. However, both recently developed LiAlP 2 O 7 :Cr 3+ (λ em = 844 nm, PLQY = 26.7%) and Al 0.5 Ta 0.5 P 2 O 7 :Cr 3+ (λ em = 850 nm, PLQY = 35.3%) exhibit ultralow PLQY values. , Obviously, more conditions should be considered to achieve an efficient Cr 3+ -activated octahedral Al 3+ -containing material. In fact, structural rigidity of host is another important factor that is widely believed to be highly correlated with PLQY of inorganic phosphor material. − Because a high rigidity of host material can inhibit soft phonon modes that result in nonradiative relaxation, thereby promoting the probability for photon emission .…”

“…However, both recently developed LiAl-P 2 O 7 :Cr 3 + (λ e m = 844 nm, PLQY = 26.7%) and Al 0.5 Ta 0.5 P 2 O 7 :Cr 3+ (λ em = 850 nm, PLQY = 35.3%) exhibit ultralow PLQY values. 23,24 Obviously, more conditions should be considered to achieve an efficient Cr 3+ -activated octahedral Al 3+ -containing material. In fact, structural rigidity of host is another important factor that is widely believed to be highly correlated with PLQY of inorganic phosphor material.…”

“…(b) Full width at half-maximum of emission spectra, and (c) normalized emission intensity as a function of Cr 3+ concentration x. (d) The PLQY comparison of this work with that in Al 0.5 Ta 0.5 P 2 O 7 :Cr 3+ (A),23 Y 0.57 La 0.72 Sc 2.71 (BO 3 ) 4 :Cr 3+ (B),46 Ga 4 GeO 8 :Cr 3+ (C),42 ScF 3 :Cr 3+ (D),45 LiInP 2 O 7 :Cr 3+ (E),47 and NaScSi 2 O 6 :Cr 3+ (F) 44. (e) Decay curves of K 2 Al 1−x Ti(PO 4 ) 3 :xCr 3+ (x = 0, 0.02, 0.04, 0.06, 0.08, 0.1, and 0.12) samples.…”