Yb/Er: Cs2Ag(In/Bi)Cl6 lead-free double perovskite for dual-modal optical temperature sensing

All Inorganic Sb3+–Ln3+‐Codoped Cs2NaYCl6 for Highly Efficient Single‐Source White‐Light Emission and Ratiometric Optical Thermometer Applications

“…It turns out that S a monotonously increases from 0.002 to 0.351 K −1 in the range of 160-360 K. Moreover, S r first increases and then gradually decreases as the temperature increases from 160 to 360 K, and S r reaches maximum of 1.59% K −1 at 260 K. The outstanding sensitivity of W1 distinguishes from the conventional rare-earth ions doped metal halide perovskite, showing the application potential in accurate ratiometric optical thermometer (Table S4, Supporting Information). [45,[48][49][50][51] As a proof-of-concept experiment, W1 was employed to prepare single-source WLEDs. The prepared W1 powders were mixed with the chloroform solution of polymethyl methacrylate (PMMA) to form a homogeneous gel.…”

Simultaneously excited downshifting/upconversion luminescence from lanthanide-doped core–shell lead-free perovskite nanocrystals for encryption and data storage

“…[23][24][25] Chen's group incorporated Yb 3+ and Er 3+ into Cs 2 AgBiCl 6 DP attempting to achieve upconversion and downshifting dual-mode PL; however, the coupling of the energy levels of Bi 3+ and Er 3+ led to a yellowgreen light emission with poor color purity. 26,27 Therefore, although Ln 3+ and transition metal ion doping can endow Cs 2 AgInCl 6 NCs with excellent optical performance, the limited color purity caused by the energy level coupling and uncontrollable energy transfer pathways between the dopants still remains to be solved, but this aspect is still lacking researchers' attention.…”

Tetrahedrally coordinated rigid crystal structure enables partial self-reduction of mixed-valence europium for optical thermometric application

“…[29][30][31] According to the configuration diagram, there is no cross point between the ground 4f 6 and excited 4f 6 parabolas due to the negligible ion-lattice interactions for Eu 3+ , making the Eu 3+ emission thermal quenching via multiphonon relaxation inaccessible. 32,33 However, the 4f 6 5d 1 electrons can strongly interact with lattice vibrations or host conduction bands on account of the outer extended Eu 2+ 4f 6 5d 1 orbits, which usually results in Eu 2+ emission being highly sensitive to temperature fluctuation. [34][35][36] Therefore, incorporating mix-valent Eu 2+ /Eu 3+ into a host, in principle, can be utilized for the of high-performance temperature sensors by employing the Eu 2+ /Eu 3+ FIR as a temperature probe.…”