Structural Rigidification Strategy Based on Self-Assembly Enabled Reversible Excited-State Conversion of Iridium(III) Complexes for Multiple-Stimulus-Responsive Data Encryption

作者：Xiangyu Liu, Jing Liu, Danlei Zhu, Xinghua Yan, Jiawei Chen, Lian Duan, Yuetong Kang, Dongxin Ma · 发表于：Journal of the American Chemical Society · 年份：2024 · DOI：10.1021/jacs.4c12454 · 被引用次数：9 · 研究领域：Luminescence and Fluorescent Materials、Organic Light-Emitting Diodes Research、Advanced Memory and Neural Computing

Stimulus-responsive chromic materials exhibit color-switching properties under specific external stimuli and have been widely used in various fields. Transition-metal complexes show great potential applications as promising candidates for stimulus-responsive chromic materials, as their excited states not only depend on the chemical composition but are also affected by the intermolecular stacking modes. Owing to the intrinsic difficulty in the ordered stacking of the octahedral configuration, changing the stacking modes of iridium(III) complexes for multiple-stimulus responsiveness remains a significant challenge. In this work, we propose a structural rigidification strategy based on self-assembly to reversibly regulate the excited states of iridium(III) complexes, therefore achieving color switch under different stimulus conditions. We prepare cationic iridium(III) complexes by using tetrakis(perfluorophenyl)-borate ([B(PhF 5 ) 4 ] − ) as the counterion, whose matching tetrahedral configuration and electron-deficient aromaticity enables polar-π interaction with the octahedral iridium(III) cations, inducing self-assembly to form structural rigidification. The structural rigidity restricts the large conformational changes of the metal-to-ligand charge transfer ( 3 MLCT) excited state, and facilitates the conversion from the 3 MLCT to the ligand-center ( 3 LC) excited state in aggregated states. The excited-state conversion results in a 54 nm blue shift (from yellow to sky blue)...