Symphony of light: AIE and MFC in carbazole-based cyanostilbenes

Abstract

In the realm of molecular design, carbazole-based cyanostilbenes have emerged as captivating conjugates, attracting researchers with their unique characteristics such as aggregation-induced emission (AIE) and mechanofluorochromism (MFC). This comprehensive review explores their distinct features, especially AIE and MFC, and provides illumination of the assumptions underlying these conjugates, their intricate structural modifications, and their potential applications. The introductory section provides a foundation for understanding solid-state emissive properties, i.e., AIE and MFC, elucidating the fundamental mechanisms driving these phenomena. Additionally, we have carefully categorised and classified various carbazole-based cyanostilbene molecules that display AIE and MFC characteristics, providing readers with a methodical summary of the variety within this fascinating family of conjugates. A substantial portion is dedicated to an in-depth analysis of the most notable examples of carbazole-based cyanostilbenes displaying AIE and MFC, emphasizing their molecular structures, and the impact of external stimuli on their optical properties in solution as well as the solid state. The most recent advances in the area are discussed, along with an in-depth investigation of the mechanisms governing AIE and MFC in these compounds, taking into account the significance of structural changes and intermolecular interactions. Additionally, this review explores the prospective uses of carbazole-based cyanostilbenes, exploring their potential in fields including bioimaging, sensors, optoelectronics and organic light-emitting diodes (OLEDs). The future outlook in these areas is discussed, offering valuable insights into the promising avenues of research and development in the years to come.