Liang Yin, Jiang Yingjie, Du Ke-Zhao, Lin Yang-Peng, Ma Xinyuan, Qiu Daping, Wang Ziyu, Hou Yanglong, Wei Xiaoding, Zhang Qing
School of Materials Science and Engineering, Peking University, Beijing 100871, China.
State Key Laboratory for Turbulence and Complex Systems, Department of Mechanics and Engineering Science, BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China.
Nano Lett. 2023 Aug 23;23(16):7599-7606. doi: 10.1021/acs.nanolett.3c02205. Epub 2023 Aug 2.
Zero-dimensional organic-inorganic metal halide hybrids provide ideal bulk-crystal platforms for exploring the pressure engineering of electron-phonon coupling (EPC) and self-trapped exciton (STE) emission at the molecular level. However, the low stiffness of inorganic clusters hinders the reversible tuning of these physical properties. Herein, we designed a Sb-doped metal halide with a high emission yield (89.4%) and high bulk modulus (35 GPa) that enables reversible and enhanced STE emission (20-fold) under pressure. The high lattice rigidity originates from the corner-shared cage-structured inorganic tetramers and ring-shaped organic ligands. Further, we reveal that the pressure-enhanced emission regime below 4.5 GPa is owing to the lattice hardening and preferably EPC strength reducing, while the pressure-insensitive emission regime within 4.5-8.5 GPa results from the enhanced intercluster Coulombic attraction force that resists intracluster compression. These results provide insights into the structure-property relation and molecular engineering of zero-dimensional metal halides toward wide-band and pressure-sensitive light sources.
零维有机-无机金属卤化物杂化物为在分子水平上探索电子-声子耦合（EPC）和自陷激子（STE）发射的压力工程提供了理想的块状晶体平台。然而，无机簇的低刚度阻碍了这些物理性质的可逆调节。在此，我们设计了一种具有高发射产率（89.4%）和高体积模量（35 GPa）的锑掺杂金属卤化物，其能够在压力下实现可逆且增强的STE发射（增强20倍）。高晶格刚性源于角共享笼状结构的无机四聚体和环状有机配体。此外，我们揭示了4.5 GPa以下压力增强发射机制是由于晶格硬化以及EPC强度优先降低，而4.5-8.5 GPa内压力不敏感发射机制是由增强的簇间库仑吸引力导致的，该吸引力抵抗簇内压缩。这些结果为零维金属卤化物向宽带和压力敏感光源的结构-性能关系及分子工程提供了见解。
