Manipulating Lone-Pair-Driven Luminescence in 0D Tin Halides by Pressure-Tuned Stereochemical Activity from Static to Dynamic

Recent strategies for triplet-state emission regulation toward non-lead organic-inorganic metal halides

Organic-inorganic metal halides (OIMHs) have strengthened the development of triplet-state emission materials due to their excellent luminescence performance. Due to the inherent toxicity of lead (Pb) significantly limiting its further advancement, numerous studies have been conducted to regulate triplet-state emission of non-Pb OIMHs, and several feasible strategies have been proposed. However, most of the non-Pb OIMHs reported have a relatively short lifetime or a low luminescence efficiency, not in favor of their application. In this review, we provide a summary of recent reports on the regulation of triplet-state emissions in non-Pb OIMHs to provide benefits for the design of innovative luminescent materials. Our focus is primarily on exploring the internal and external factors that influence the triplet-state emission. Starting from the luminescence mechanism, the current strategies for regulating triplet-state emissions are summarized. Moreover, by manipulating these strategies, it becomes feasible to achieve triplet-state emissions that span a range of colors from blue to red, and even extend into the near-infrared spectrum with high luminescence efficiency, while also increasing their lifetimes. This review not only provides fresh insights into the advancement of triplet-state emissions in OIMHs but also integrates experimental and theoretical perspectives to illuminate the trajectory of future research endeavors.

Multi-stimuli-responsive luminescence enabled by crown ether anchored chiral antimony halide phosphors

Stimuli-responsive optical materials have provided a powerful impetus for the development of intelligent optoelectronic devices. The family of organic-inorganic hybrid metal halides, distinguished by their structural diversity, presents a prospective platform for the advancement of stimuli-responsive optical materials. Here, we have employed a crown ether to anchor the A-site cation of a chiral antimony halide, enabling convenient control and modulation of its photophysical properties. The chirality-dependent asymmetric lattice distortion of inorganic skeletons assisted by a crown ether promotes the formation of self-trapped excitons (STEs), leading to a high photoluminescence quantum yield of over 85%, concomitant with the effective circularly polarized luminescence. The antimony halide enantiomers showcase highly sensitive stimuli-responsive luminescent behaviours towards excitation wavelength and temperature simultaneously, exhibiting a versatile reversible colour switching capability from blue to white and further to orange. In situ temperature-dependent luminescence spectra, time-resolved luminescence spectra and theoretical calculations reveal that the multi-stimuli-responsive luminescent behaviours stem from distinct STEs within zero-dimensional lattices. By virtue of the inherent flexibility and adaptability, these chiral antimony chlorides have promising prospects for future applications in cutting-edge fields such as multifunctional illumination technologies and intelligent sensing devices.

Time-Resolved Dynamics of Metal Halide Perovskite under High Pressure: Recent Progress and Challenges

Metal halide perovskites have garnered significant attention in the scientific community for their promising applications in optoelectronic devices. The application of pressure engineering, a viable technique, has played a crucial role in substantially improving the optoelectronic characteristics of perovskites. Despite notable progress in understanding ground-state structural changes under high pressure, a comprehensive exploration of excited-state dynamics influencing luminescence remains incomplete. This Perspective delves into recent advances in time-resolved dynamics studies of photoexcited metal halide perovskites under high pressure. With a focus on the intricate interplay between structural alterations and electronic properties, we investigate electron-phonon interactions, carrier transport mechanisms, and the influential roles of self-trapped excitons (STEs) and coherent phonons in luminescence. However, significant challenges persist, notably the need for more advanced measurement techniques and a deeper understanding of the phenomena induced by high pressure in perovskites.