Blue and Second Near-Infrared Transmissive Electrochromic Polymers based on ProDOT and Triphenylamine Derivatives

Electrochromic materials have recently aroused extreme attention due to their exceptional application potential in display screens, architectural glass, and coating stealth materials, etc. Developing electrochromic polymers synchronously sharing blue and second near-infrared (NIR-II) transmissive is urgently in demand but extremely scarce. Herein, three kinds of electrochromic polymers featuring redox electrochemical and electrochromic properties are obtained through electrochemical polymerization of three monomers, ProDOT-TPA, ProDOT-TPPA, and ProDOT-2TPA, which are constructed based on 3,4-ethylenedioxythiophene (ProDOT) and triphenylamine (TPA) derivatives. Electrochemical studies reveal that ProDOT-TPA exhibits low initial oxidation potential of 0.59 V, possessing significant advantages for obtaining high-quality polymers. The optimized polymers [P(ProDOT-TPA)] show significant properties in electrochromic devices with optical contrast of 14.38% at 400 nm and 49.55% at 1100 nm, along with coloration efficiency of 123 cm²C^-1 and response times of 0.5 s.