Dual polymer electrochromic sunglasses with black to anti-blue-ray conversion based on new anti-blue-ray transparent polymer

Smart electrochromic (EC) glasses with visible light modulation have attracted considerable attention due to their unique advantages, but EC sunglasses with anti-blue-ray function have not yet been reported. Herein, a series of wide-bandgap electrochromic conjugated polymers P2–P4 based on 3,4-propylenedioxythiophene (ProDOT) and naphthalene units were designed and synthesized using direct arylation polymerization. Among them, polymers P2 exhibit a satisfactory yellow hue and outstanding overall electrochromic performances. By tuning the intramolecular torsion between ProDOT and naphthalene units in the polymer structure, the absorption spectra of polymers P3 were entirely shifted to the high-energy violet-blue spectra region relative to the anti-blue-ray function. New dual conjugated polymer electrochromic devices based on P3 and black-to-transmissive electrochromic polymer were fabricated, which exhibited the fast transformation between black and anti-blue-ray transmissive color with a switching time of < 5.0 s, high contrast of 49% at 400–700 nm and a high coloring efficiency of 470.8 cm2/C. Moreover, an EC prototype sunglasses device with an anti-blue-ray function was fabricated to demonstrate the practical suitability based on the dual conjugated polymer ECDs. This work contributes to the application of EC technology to the smart glasses field.