压致变色聚集诱导发光材料

Piezochromic Aggregation-Induced Emission Materials

压致发光变色材料是在外力作用下,发光颜色发生明显改变的一类智能材料,包括压致荧光变色材料和压致磷光变色材料。压致发光变色材料在应力传感、信息存储、商品防伪和发光器件等领域具有重要的潜在应用前景,近年来,受到了人们极大的关注。但是,已经报道的压致发光变色材料非常稀少。可能的原因有两个,一是没有分子结构与压致发光变色性能关系的规律来指导压致发光变色化合物的合成;二是一般的发光化合物由于具有聚集发光猝灭效应导致在固体状态下很难观察到压致发光变色现象。直到近两年我们发现聚集诱导发光化合物与压致发光变色化合物之间具有结构上的关联性并提出压致变色聚集诱导发光材料的概念之后,许多压致变色聚集诱导发光材料被陆续报道。聚集诱导发光材料成为压致发光变色材料一个非常重要的来源。本文总结了近年来关于压致变色聚集诱导发光材料的研究进展情况,对聚集诱导发光材料的压致变色机理、结构与性能关系以及潜在的应用进行了阐述。

Piezochromic （machanochromic） luminescent materials are a class of ＂smart＂ materials with luminescent properties that change in response to external force stimuli. These materials are widely used in many fields such as mechanosensors, memory chips, security inks and optoelectronic devices, and have attracted considerable interest in recent years. However, the piezochromic luminescent materials that are dependent on changes in physical molecular packing modes are extremely rare. This rarity may be attributed to two major issues. First, a common method for piezochromic luminescent compound synthesis is not to be realized. Each identified compound is an isolated event, rendering difficulty in the identification of a general characteristic. Second, the fluorescence efficiency of organic luminescent materials often becomes very weak while in solid state because of the aggregation-caused quenching effect. Consequently, the piezochromic luminescent phenomenon becomes difficult to observe. Until the last two years, we recognized the existence of a structural relationship between the aggregation-induced emission compound and the piezochromic luminescent nature, and put forward the concept of ＂piezochromic aggregation-induced emission materials＂, many piezochromic aggregation-induced emission materials have been reported one after another. Aggregation-induced emission compounds can be expected to become an important source of piezochromic luminescent materials, and in other words piezochromic luminescent materials would no longer be rare in the future. In this review, recent progress in the area of piezochromic aggregation-induced emission materials is summarized, and majority of the reported piezochromic aggregation-induced emission systems are discussed, including concept, mechanism, structure-property relationship, application, and so on.