Water-Soluble Hyperbranched Polyamidoamine Bearing Viologen Groups toward Electrochromic/Electrofluorochromic Dual-Mode Aqueous Phase Devices

The health and environmental concerns drive the exploration of electro-optical materials featuring aqueous processability and environmental friendliness. This work presents a water-soluble electroactive hyperbranched polyamidoamine toward electrochromic (EC)/electrofluorochromic (EFC) dual-mode aqueous phase devices. The resultant polymer bearing viologen groups exhibit reversible electroactivity and desirable EC properties (Δ T % = 71.7%, coloration efficiency (CE) = 216 cm 2 C −1 ). The aggregation-induced quenching as well as the energy transfer between the electroactive viologen groups and autofluorescent tertiary amine units results in a simultaneous EFC behavior with acceptable fluorescence contrast (on/off = 8.5) and moderate switching speed (22.9/12.5 s). Furthermore, a reflective/emissive dual-mode aqueous phase device is manufactured readily based on the resultant polymer, which displays a simultaneous EC and EFC performance with high optical contrast (Δ T % = 92%), moderate fluorescence contrast (4.5), competitive CE (108 cm 2 C −1 ), and low switching voltage of −1.4 V.