Bipyridinium-Bearing Multi-stimuli Responsive Chromic Material with High Stability

Interests in chromic materials are rapidly increasing for their potential applications as smart responsive materials. However, the majority of the existing ones are triggered by merely one or two outer stimuli and the few multi-stimuli responsive examples still suffer from their confining functioning state such as solution or polymer. To address these challenges, a new generation of multi-stimuli responsive chromic materials is being intensively pursued. In this article, we report a neoteric supramolecular solid material by assembling Co(II) ion with bipyridinium-functionalized ligand in solvothermal condition. This material can perform reversible chromic behaviors in response to 365 nm light, heat, vacuum, ammonia, ethanediamine, and some organic solvents. Meanwhile, it exhibits excellent structural stability and reversibility to cope with these stimuli.