Distortion induced structural characteristics of Ba₂R_2/3TeO₆(R = Y, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) double perovskites and their multifunctional optical properties for lighting and ratiometric temperature sensing

Abstract

Monoclinic (P21/n) structure of B-site ordered double perovskites Ba2R2/3TeO6 (R = Y, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) is elucidated from XRD, Raman and IR spectroscopy. The maximum relative temperature sensitivity of Ba2Y2/3TeO6:Eu3+ between 300–500 K is 0.18% K−1.

Vibrationally Induced Photophysical Response of Sr2NaMg2V3O12:Eu3+ for Dual‐Mode Temperature Sensing and Safety Signs

“…To provide a more detailed analysis, the radiative and nonradiative decay rates at various temperatures were calculated using 4 f –4 f intensity theory. [ 57–65 ] The total radiative decay rate ( A R ) is estimated by taking the sum of radiative rates A 0 J for each 5 D 0 – 7 F J transition given bywhere υ 01 and υ 0 J are frequencies and I 01 and I 0 J are the integrated intensities of the 5 D 0 – 7 F 1 and 5 D 0 – 7 F J transitions and A 01 is the Einstein coefficient between the 5 D 0 and 7 F 1 levels. Using the observed lifetime τ obs of the 5 D 0 level, the nonradiative decay rate, A NR , is calculated by …”

“…At the same time, the almost constant decay time of Eu 3þ implies that a pronounced To provide a more detailed analysis, the radiative and nonradiative decay rates at various temperatures were calculated using 4f-4f intensity theory. [57][58][59][60][61][62][63][64][65] The total radiative decay rate (A R ) is estimated by taking the sum of radiative rates A 0J for each 5 D 0 -7 F J transition given by…”

Synthesis and optical spectroscopy of Na3Y(VO4)2:Eu3+ phosphors for thermometry and display applications

“…This value clearly confirms the high thermal stability of NYVO:0.15Eu 3+ phosphor. Clearly, the thermal activation energy of NYVO:0.15Eu 3+ is greater than that of certain previously reported phosphors, such as BaZrGe 3 O 9 :Eu 3+ (0.18 eV), 43 Ba 2 Y 2/3 TeO 6 :Eu 3+ (0.15 eV), 44 Sr 2 MgTeO 6 :Eu 3+ (0.27 eV), 45 LiSrBiTeO 6 :Eu 3+ (0.29 eV) 46 showing that NYVO:Eu 3+ phosphor has strong thermal stability.…”

Deep‐red‐emitting SrLaLiTeO6: Mn4+ double perovskites: Correlation between Mn4+‐O2− bonding and photoluminescence

“…were explored and its optical properties, thermal stability, etc. were investigated to establish its comparable performance with that of other double perovskite oxides as potential red phosphors 7,8,23–27 . Also, far‐red‐emitting phosphors such as LiLaMgTeO 6 : Mn 4+ , NaMgLaTeO 6 : Mn 4+ , etc.…”

“…were investigated to establish its comparable performance with that of other double perovskite oxides as potential red phosphors. 7,8,[23][24][25][26][27] Also, far-red-emitting phosphors such as LiLaMgTeO 6 : Mn 4+ , NaMgLaTeO 6 : Mn 4+ , etc. were explored for plant growth LED applications.…”