Photo-electrochemical stability, rapid switching time, and mechanical durability are key factors in achieving high-performance flexible and large-area electrochromic (EC) devices. However, the typically used counter electrode of indium tin oxide (ITO) are prone to degradation after repeated redox cycling and reiterative bending stress. This study introduces a heterogeneous structure that incorporates modified poly(3,4-ethylenedioxythiophene) (m-PEDOT) as the organic electrochromic material and a tungsten trioxide (WO₃) film in the counter electrode of ITO, which serves as both an ion storage layer and a protective layer. The WO₃-based EC devices achieved a maximum optical modulation (ΔT) of 51 % at 631 nm, significantly higher than the 17 % (ΔT) observed in devices without WO₃. Additionally, the device demonstrated fast switching times of 1.2 s for bleaching and 6.3 s for coloring, with a high coloring efficiency of 474 cm²/C. Durability tests revealed a 98 % recovery in optical modulation after 500 cycles, and strong mechanical stability after 100 bending cycles. The fabrication of a 1170 cm² flexible device confirms the practical viability of this approach, enhancing both electrochemical and optical properties for large-scale applications such as smart windows.

中文翻译：

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可扩展的柔性电致变色器件，具有基于 WO3 的离子存储层，可增强光调制和稳定性


光电化学稳定性、快速开关时间和机械耐久性是实现高性能柔性和大面积电致变色 （EC） 器件的关键因素。然而，通常使用的氧化铟锡 （ITO） 对电极在反复氧化还原循环和重复弯曲应力后容易降解。本研究介绍了一种异质结构，该结构将改性聚（3,4-乙烯二氧噻吩）（m-PEDOT）作为有机电致变色材料，并在 ITO 的对电极中加入三氧化钨 （WO ₃ ） 膜，该膜既用作离子存储层又用作保护层。基于 WO ₃ 的 EC 器件在 631 nm 处实现了 51% 的最大光调制 （ΔT），明显高于在没有 WO ₃ 的器件中观察到的 17% （ΔT）。此外，该设备表现出 1.2 秒的漂白和 6.3 秒的快速着色时间，着色效率高达 474 厘米 ² /摄氏度。耐久性测试表明，500 次循环后光调制恢复 98%，弯曲 100 次循环后具有很强的机械稳定性。1170 厘米 ² 柔性器件的制造证实了这种方法的实际可行性，增强了智能窗户等大规模应用的电化学和光学特性。