Reversible Mechanically Induced On–Off Photoluminescence in Hybrid Metal Halides

Abstract

Stimulus-responsive photoluminescent materials have attracted extensive research attention in recent years owing to their potential application in information storage and switch devices. It is important to further explore such bistable materials as well as the underlying transformation mechanisms. Herein, the syntheses and mechanically tunable "on-off" photoluminescence (PL) of two organic-inorganic hybrid metal halides, (Bmpip) 9 Pb 3 Zn 2 Br 19 and (Bmpip) 9 Pb 3 Cd 2 Br 19 (Bmpip + = 1-butyl-1-methyl-piperidinium, C 10 H 22 N + ), are reported. Both as-obtained compounds are nonemissive under UV light at ambient conditions but exhibit bright PL upon grinding or under hydrostatic pressure. Interestingly, the PL is quenchable by short-time annealing or storage in air for 1 week, and the process is repeatable. Through a combination of extensive structural and spectral analyses, the crucial role of the organic cations interacting with inorganic chromophores in the "on-off" PL behavior of the title compounds is revealed. Moreover, pressure-induced PL and PL-enhancement phenomena are observed in both compounds, which are similar to but slightly different than the above-mentioned mechano-PL. Finally, proof-of-concept devices are fabricated to demonstrate the potential applications of the title compounds in message recording and force sensing.

Photoluminescent Properties of Two-Dimensional Manganese(II)-Based Perovskites with Different-Length Arylamine Cations

“…Temperature-dependent PL characterization of 1−4 was performed under ∼417 nm excitation (Figures 3 and S5). 43 Compounds 1−3 exhibited a single LE emission at 77 K, and the HE peak in 4 also weakened significantly at 77 K. This phenomenon proved that the main emission mechanism at low temperature was the d−d transition of Mn 2+ . As the temperature increased, the electrons in [MnCl 6 ] 4− could gain enough energy to transfer back to the excitation energy level of the organic cations, so the intensity of the HE peaks was enhanced.…”

Reversible human-temperature-responsive luminescence switching in a Mn(ii)-based metal halide

“…Stimuli-responsive luminescent materials, with a specific response to external stimuli such as light, 1 pressure, 2 solvent molecules, 3 and heat, 4,5 have attracted extensive research interest and have shown wide application potentials in information storage, 6–8 chemical sensing, 9–11 and anti-counterfeiting. 12–15 In particular, thermosensitive materials are praised for their simple heating device requirement, highlighting their applications in thermal imaging, and thermometers.…”

Reversible Luminescent Switching Induced by Heat/Water Treatment in a Zero-Dimensional Hybrid Antimony(Ⅲ) Chloride

“…In addition, 0-D IOMHs may own soft lattice and strong electron–phonon coupling, thus leading to interesting photoluminescent properties, including broad emission and large Stokes shift [ 10 ]. As a result, the applications of photoluminescent 0-D IOMHs have flourished in light-emitting diode [ 11 , 12 , 13 , 14 , 15 ], X-ray scintillator [ 16 , 17 , 18 ], remote thermography [ 19 , 20 ], optical waveguide [ 21 ], anti-counterfeiting [ 22 , 23 , 24 , 25 , 26 ], as well as sensor [ 27 , 28 , 29 , 30 ].…”