Yin Yanxue, Wang Yixuan, Zhang Ting, Yang Yunfeng, Wang Weibin, Yang Binhao, Yang Qing, Xiao Zhihao, Yang Xinyi
Synergetic Extreme Condition High-Pressure Science Center, State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China.
Chem Asian J. 2025 Jun;20(11):e202401784. doi: 10.1002/asia.202401784. Epub 2025 Apr 9.
Lanthanide metal-organic frameworks (Ln-MOFs) exhibit distinctive emission spectra and prolonged luminescent lifetimes, thereby offering a unique platform for the advancement of solid-state photoluminescence (PL) materials. However, the mismatch between the energy levels of metal ions and organic ligands leads to a weak PL emission. Herein, this study presents a pressure-treated strategy aimed at achieving efficient green PL in Tb(BDC)(HO) MOF. Compared to the initial intensity, the PL intensity is enhanced eightfold below 3.1 GPa. Intriguingly, the PL intensity of pressure-treated sample is amplified by 2.5-fold compared to the initial state, and the green emission monochromaticity is maintained. Experiments and calculations reveal that the enhanced hydrogen bonds are retained to the ambient conditions after pressure treatment. They lock the conjugated configuration formed between the planes of carboxyl group and benzene ring, facilitating the intersystem crossing. The reduced distances between metal ions and organic ligands drive the ligand-to-metal energy transfer process. This finding provided significant insights into structure-property relationship of Tb(BDC)(HO), offering a new platform for boosting emission enhancement in Ln-MOFs.
镧系金属有机框架材料（Ln-MOFs）具有独特的发射光谱和较长的发光寿命，从而为固态光致发光（PL）材料的发展提供了一个独特的平台。然而，金属离子和有机配体的能级不匹配导致PL发射较弱。在此，本研究提出了一种压力处理策略，旨在实现Tb(BDC)(HO) MOF中的高效绿色PL。与初始强度相比，在3.1 GPa以下PL强度提高了八倍。有趣的是，压力处理样品的PL强度与初始状态相比放大了2.5倍，并且绿色发射单色性得以保持。实验和计算表明，压力处理后增强的氢键在环境条件下得以保留。它们锁定了羧基平面和苯环平面之间形成的共轭构型，促进了系间窜越。金属离子与有机配体之间距离的减小推动了配体到金属的能量转移过程。这一发现为Tb(BDC)(HO)的结构-性能关系提供了重要见解，为提高Ln-MOFs的发射增强提供了一个新平台。
