Molecular engineering of D-A-D type thiophen-based polymers consisting of quinoline moieties for electrochromism and energy storage

Abstract

Three D-A-D type thiophene-based monomers (HDMQT, HDPQT and HPAQT) with different quinoline-based acceptors were prepared and further electrochemical polymerized to deposite on ITO substrates as electrodes. The present conjugated polymer thin films PHDMQT, PHDPQT and PHPAQT showed efficient electrochromic and energy storage performance. Among them, PHDMQT exhibited fast electrochromic switch with short response time less than 0.5 s, and an optical contrast of 39%, high coloration efficiency over 259 cm2/C, as well as good cycling stability. Moreover, quasi-solid state electrochromic storage devices based on the present polymers employing gel-type electrolyte were fabricated, and exhibiting distinct color-changing effects during charging and discharging cycles, which suggested their potential applications in energy saving smart windows.