Recent advances in aggregation-induced emission of mechanochromic luminescent organic materials

Abstract

Mechanochromic luminogenic materials (MCL) can reversibly modify their luminescence properties when exposed to external mechanical stimuli. This smart effect could emerge from physico-chemical characteristics varying in a wider scale, ranging from the transformation of molecular domains to the rearrangement of chemical bonds. MCL has become the fast-emerging group of materials owing to their great application potential as stress sensors, smart switches, optical memories, and optoelectronic and display devices. In recent years, a lot of work has been carried out on these materials leading to the synthesis of various MCL materials. This review discusses various organic MCL materials and their underlying luminogenic mechanisms. Furthermore, a detailed literature review of how different classes of luminescent organic materials respond to mechanical forces has been provided. In particular, the most common chromophores used in such systems including triphenylamine, cyanoethylene, pyrene, tetraphenylethene, and others are described here with an emphasis on their industrial applications. Presumably, this review will provide useful insights into the characteristics and applications of MCL materials to researchers working in this field in the academic community and industry.