Substituent effects of AIE-active α-cyanostilbene-containing triphenylamine derivatives on electrofluorochromic behavior.

Four aggregation-induced emission (AIE)- and electro-active cyanostilbene-based triphenylamine-containing derivatives with different substituents were synthesized to investigate their effects on the photoluminescence properties and electrochromic (EC) and electrofluorochromic (EFC) behavior of gel-type electrochromic devices (ECDs). The optical and photoluminescence properties of the obtained materials were influenced by the substituents, and revealed AIE-active characteristics, exhibiting stronger fluorescence intensity in the aggregated state than in solution. Consequently, the EFC devices could be fabricated by combining these AIE- and electro-active materials with cathodic EC heptyl viologen HV into the gel-type electrolyte system to enhance the emission intensity, on/off contrast ratio, and response capability.