Enhancing luminescence intensity and improving thermostability of red phosphors Li3Ba2La3(WO4)8:Eu3+ by co-doping with Sm3+ ions

A novel scheelite‐type LiCaGd(WO4)3:Eu3+ red phosphors with prominent thermal stability and high quantum efficiency

“…The measuring principle of quantum efficiency can be expressed by the following equation 39,40 : $$$$\begin{equation}{\eta _{QE}} = \frac{{\int {{L_S}} }}{{\int {{E_R} - \int {{E_S}} } }},\end{equation}$$$$where L S is the PL spectrum of the phosphor, and E S and E R denote the PLE light with and without the phosphor in the integrating sphere, respectively. Under the 395 nm PLE, the quantum efficiency of LCGWO: x Eu 3+ phosphors rises gradually with Eu 3+ doping concentration, and it reaches 94.2% when x = 1.0, which is higher than Ba 2 Y 5 B 5 O 17 :Eu 3+ (47.2%), 41 K 5 Bi(Mo x W 1‐ x O 4 ) 4 :Eu 3+ (45.7%), 42 Li 3 Ba 2 La 3 (WO 4 ) 8 :Eu 3+ (53%), 43 and NaGd(WO 4 ) 2 :Eu 3+ (67.2%) 44 . Thus, LCGWO: x Eu 3+ phosphors with a high doped concentration can be proved to have excellent luminescence property and high efficiency.…”

Thermal-stability synergy improvement of Sm3+ and Eu3+ in Ca3.6In3.6(PO4)6: the effect of local symmetry

“…Under 396 nm excitation, the IQE of CI 1− x − y P:0.05Eu 3+ ,0.04Sm 3+ phosphors reached 82.8%, which was higher than those of other red phosphors, such as NaLaP 4 O 12 :Sm 3+ (IQE = 38.8%), Na 2.5 Zr 2 Si 1.5 P 1.5 O 12 :Eu 3+ (IQE = 72.14%), and Li 3 Ba 2 La 3 (WO 4 ) 8 :Eu 3+ , Sm 3+ (IQE = 53%), etc. 15,44,45 As a preliminary application, CI 1− x − y P:0.05Eu 3+ ,0.04Sm 3+ phosphor was used to fabricate the LED chip to further prove its potential application for WLEDs. Fig.…”

“…The value of the IQE is calculated as follows: 35 where L S represents the emission spectrum of CI 1ÀxÀy (IQE = 53%), etc. 15,44,45 As a preliminary application, CI 1ÀxÀy P: 0.05Eu 3+ ,0.04Sm 3+ phosphor was used to fabricate the LED chip to further prove its potential application for WLEDs. Ra value (86.9) and low CCT (4694 K).…”

“…11 Owing to the potential energy transfer from Sm 3+ to Eu 3+ , the Sm 3+ ion has been utilized as a sensitizer in Eu 3+ -activated red phosphors. [12][13][14] Interestingly, the co-doping of Sm 3+ improved the thermal stability of Eu 3+ in both Li 3 Ba 2 La 3 (WO 4 ) 8 15 and SrBi 2 B 2 O 7 . 12 Herein, this co-doping method can be defined as homogeneity co-doping because of the luminous similarity between Sm 3+ and Eu 3+ .…”

“…Interestingly, the co-doping of Sm 3+ improved the thermal stability of Eu 3+ in both Li 3 Ba 2 La 3 (WO 4 ) 8 15 and SrBi 2 B 2 O 7 . 12 Herein, this co-doping method can be defined as homogeneity co-doping because of the luminous similarity between Sm 3+ and Eu 3+ .…”