High-performance Electrochromic Supercapacitor Based on a New EDOT-triphenylamine Conjugated Polymer

Despite the rapid advancement of electrochromic capacitive energy storage, there are still challenges in simul-taneously improving electrochemical kinetics and cycling stability. Here we synthesize a new conjugated poly-mer bearing twisted EDOT-triphenylamine (TPA) dual-redox centers through facile electropolymerization. Benefiting from the multiple electroactive segments, the resultant polymer electrode reveals remarkable multi-color electrochromism (from yellow to green and blue) and concurrently good capacitive energy storage (high capacitance of 39 mF cm-2). The twisted alignment of the TPA structure facilitates ions diffusion and electro-chemical reaction kinetics. Coupled with vanadium pentoxide ion-storage material, an assembled asymmetric electrochromic supercapacitor device (AESD) displays a high optical contrast of 71.37%, a wide voltage window of 2 V, the desirable energy density of 20.2 mu Wh cm-2, and outstanding cycling durability (87% capacitance after 6000 cycles at 0.2 mA cm-2). This method and knowledge offered by density functional theory (DFT) provide another path toward improving electrochromic and capacitive performance in a synergetic manner.