Recent progress on the construction and application of dithienylethene-based photochromic AIEgens

Photochromic fluorescent materials have rapidly developed as a new class of intelligent materials, offering a unique combination of traditional photochromic and organic fluorescent materials. These materials possess remarkable photoresponsiveness that can be observed by the naked eye and exhibit fluorescence color change. Consequently, they have found widespread applications in various domains, including molecular switches, logic encryption, medical diagnosis and treatment, and biosensors. Among the multitude of photochromic systems, those based on dithienylethenes (DTEs) have garnered significant attention due to their exceptional photochromic efficiency, commendable reversible photoresponse and fatigue resistance, as well as excellent photostability and thermal stability. Nevertheless, these photochromic fluorescent materials continue to grapple with the issue of aggregation-caused quenching (ACQ), a common problem faced by traditional fluorescent materials. Therefore, the integration of DTE systems with aggregation-induced emission (AIE) systems presents a promising solution to tackle this predicament, enabling an improved quantum yield for photochromic fluorescent materials in their aggregated state and broadening their range of applications. This review comprehensively summarizes and evaluates the construction strategies and application prospects of DTE-based photochromic AIE luminogens (AIEgens) in recent years, while also providing an outlook on their future development.