Liu Haichao, Gu Yarong, Dai Yuxiang, Wang Kai, Zhang Shitong, Chen Gang, Zou Bo, Yang Bing
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Changchun 130012 , P. R. China.
State Key Laboratory of Superhard Materials, College of Physics , Jilin University , Changchun 130012 , P. R. China.
J Am Chem Soc. 2020 Jan 22;142(3):1153-1158. doi: 10.1021/jacs.9b11080. Epub 2020 Jan 13.
Most organic piezochromic materials exhibit red-shifted and quenched emission as pressure increases. However, an abnormal phenomenon of pressure-induced blue-shifted and enhanced emission is observed in a 9-(3-(1,2,2-triphenylvinyl)phenyl)anthracene crystal, which is based on discrete π-π anthracene (AN) dimers stacking with tetraphenylethylene (TPE) as spacer. A blue-shifted emission appears and strengthens when the pressure is more than 1.23 GPa, and it reaches the maximum when the pressure is 4.28 GPa. This phenomenon is ascribed to the cooperative effect between the aggregation-induced emission of TPE units and energy-transfer suppression from TPE to an AN excimer. This work reports a new concept in the piezochromic field and provides a novel strategy to achieve luminescence from a high-lying excited state.
大多数有机压致变色材料随着压力增加呈现发射峰红移和荧光猝灭现象。然而，在一种9-(3-(1,2,2-三苯基乙烯基)苯基)蒽晶体中观察到了压力诱导发射峰蓝移和荧光增强的异常现象，该晶体基于以四苯乙烯（TPE）为间隔基的离散π-π蒽（AN）二聚体堆积结构。当压力超过1.23 GPa时，发射峰出现蓝移并增强，在压力为4.28 GPa时达到最大值。这种现象归因于TPE单元的聚集诱导发光与从TPE到AN准分子的能量转移抑制之间的协同效应。这项工作报道了压致变色领域的一个新概念，并提供了一种从高能激发态实现发光的新策略。
