Deciphering crystal structure and photophysical response of Bi3+ and Pr3+ co-doped Li3Gd3Te2O12 for lighting and ratiometric temperature sensing

Augmenting cyan emission in vanadate garnets via Dy3+activation for light emitting devices and multi-mode optical thermometry

“…Over the years, light-emitting devices based on solid-state technology have made profound advancements in lighting due to their benefits, such as energy efficiency, an extended lifetime, low energy consumption, environmental friendliness, and so on. [1][2][3][4] Nevertheless, the commercially available devices based on a blue LED and yellow phosphor, YAG:Ce 3+ , are limited by their low color rendering index due to the lack of the red emission component. As a solution to this problem, the combination of red-green-blue phosphors with the NUV chip is introduced.…”

“…12,13 In various vanadate-based phosphor systems, the garnet structure offers more freedom to tune the emission owing to the unique structural framework, flexibility in cation substitution, and compositional diversity. 1,4,14 The general stoichiometry of the garnet structure is A 3 B 2 C 3 O 12 where A, B, and C correspond to dodecahedral, octahedral, and tetrahedral sites. In particular, for vanadate garnets, the tetrahedral complex VO 4 3− is interlinked with the structural changes in the neighborhood.…”

“…1,4,14 The general stoichiometry of the garnet structure is A 3 B 2 C 3 O 12 where A, B, and C correspond to dodecahedral, octahedral, and tetrahedral sites. In particular, for vanadate garnets, the tetrahedral complex VO 4 3− is interlinked with the structural changes in the neighborhood. Another added advantage of the vanadate garnet host is the low phonon energy, which helps in achieving better luminescence properties.…”

“…14 Furthermore, it is quite important to tune the emission towards the cyan region via the energy transfer strategy using activator ions. In this context, Dy 3+ is selected as the activator owing to its significant emission in the blue and yellow regions due to the magnetic 4 F 9/2 → 6 H 15/2 and electric dipole 4 F 9/2 → 6 H 13/2 transitions, respectively. In addition, tuning of yellow and blue bands can be done easily in Dy 3+ based garnet systems.…”

Temperature sensing of Sr3Y2Ge3O12:Bi3+,Sm3+ garnet phosphors with tunable sensitivity

“…19,20 The FIR-type optical thermometers in garnet hosts have been widely reported. [21][22][23][24][25][26][27][28] However, research on the potential of Sr 3 Y 2 Ge 3 O 12 garnets in the field of temperature measurement has not been reported yet. 29 Based on the principle of FIR temperature sensing with dual emission centres, the combination of Bi 3+ and Sm 3+ for co-substitution in Sr 3 Y 2 Ge 3 O 12 was chosen for two reasons.…”