Abnormal Pressure‐Induced Photoluminescence Enhancement and Phase Decomposition in Pyrochlore La₂Sn₂O₇

Abstract

La Sn O is a transparent conducting oxide (TCO) material and shows a strong near-infrared fluorescent at ambient pressure and room temperature. By in situ high-pressure research, pressure-induced visible photoluminescence (PL) above 2 GPa near 2 eV is observed. The emergence of unusual visible PL behavior is associated with the seriously trigonal lattice distortion of the SnO octehedra, under which the Sn-O1-Sn exchange angle θ is decreased below 22.1 GPa, thus enhancing the PL quantum yield leading to Sn P → S photons transition. Besides, bandgap closing followed by bandgap opening and the visible PL appearing at the point of the gap reversal, which is consistent with high-pressure phase decomposition, are discovered. The high-pressure PL results demonstrate a well-defined pressure window (7-17 GPa) with flat maximum PL yielding and sharp edges at both ends, which may provide a great calibration tool for pressure sensors for operation in the deep sea or at extreme conditions.

Harvesting Cool Daylight in Hybrid Organic–Inorganic Halides Microtubules through the Reservation of Pressure‐Induced Emission

“…[13,14] Pressure is a powerful strategy to profoundly reduce interatomic distances and modify bonding patterns, thus creating fascinating materials not accessible under atmospheric conditions. [15][16][17][18][19][20][21][22][23] Pressure-induced emission (PIE) was first identified in compressed 0D perovskite Cs 4 PbBr 6 nanocrystals. [24] Thereafter, this exotic PIE was also discovered in 1D C 4 N 2 H 14 SnBr 4 , C 4 N 2 H 14 PbBr 4 and 2D (CH 3 (CH 2 ) 3 NH 3 ) 4 AgBiBr 8 .…”

Structural Stability of Pyrochlore Manganate In2Mn2O7 Under High Pressure

“…The P-V data were fitted using the Birch-Murnaghan (B-M) equation of state [32], expressed as follows: ) GPa [33,34], and the bulk moduli of A 2 Sn 2 O 7 (A La, Eu) compounds were 180(6) and 170 GPa, respectively [35]. It can be seen that the bulk modulus of In 2 Mn 2 O 7 was obviously larger than that of the above compounds.…”

Supersensitive Ratiometric Thermometry and Manometry Based on Dual‐Emitting Centers in Eu2+/Sm2+‐Doped Strontium Tetraborate Phosphors

“…[24] Upon high-pressure compression, materials experience various changes, such as the shrinkage of the unit cell, the shortening of chemical bonds, the variation of local symmetry of atoms/ions, the formation of crystal defects and even the appearance of new compounds after pressure-induced phase transformations. [25][26][27][28][29] As a consequence, the development of new, high-sensitivity pressure probes, operating in a wide pressure range is a challenging task. Currently, to optically monitor pressure with luminescent materials, the spectroscopic parameters, such as the band position (line shift), the emission lifetime and the bandwidth are mainly used, as their values may change monotonously with pressure.…”