High-performance D–π–A–π–D type electrochromic polymers based on nitro-substituted triphenylamine derivatives with thiophene and EDOT as π bridges

PETTPA exhibited a reversible and stable color change from dark brown to dark blue with a favorable optical contrast of 41% at 1100 nm and a high coloration efficiency of 332.6 cm 2 C −1 with an extremely fast response time of 0.3 seconds.