Abstract：
Electrochromic devices (ECDs), which are capable of modulating optical properties in the visible and long-wave infrared (LWIR) spectra under applied voltage, are of great significance for military camouflage. However, there are a few materials that can modulate dual frequency bands. In addition, the complex and specialized structural design of dual-band ECDs poses significant challenges. Here, we propose a novel approach for a bendable ECD capable of modulating LWIR radiation and displaying multiple colors. Notably, it eliminates the need for a porous electrode or a grid electrode, thereby improving both the response speed and fabrication feasibility. The device employs multiwalled carbon nanotubes (MWCNTs) as both the transparent electrode and the LWIR modulator, polyaniline (PANI) as the electrochromic layer, and ionic liquids (HMIM[TFSI]) as the electrolyte. The ECD is able to reduce its infrared emissivity (Δε = 0.23) in a short time (resulting in a drop in infrared temperature from 50 to 44 °C) within a mere duration of 0.78 ± 0.07 s while changing its color from green to yellow within 3 s when a positive voltage of 4 V is applied. In addition, it exhibits excellent flexibility, even under bending conditions. This simplified structure provides opportunities for applications such as wearable adaptive camouflage and multispectral displays.
摘要：
电致变色装置(ECD),它们能够在施加电压下调制可见和长波红外（LWIR）光谱中的光学特性，对军事伪装具有重要意义。然而,有一些材料可以调制双频带。此外,双频带电子CD的复杂和专业的结构设计提出了重大挑战。这里,我们提出了一种能够调节LWIR辐射并显示多种颜色的可弯曲ECD的新方法。值得注意的是,它消除了对多孔电极或网格电极的需要，从而提高了响应速度和制造可行性。该装置采用多壁碳纳米管（MWCNT）作为透明电极和LWIR调制器，聚苯胺(PANI)作为电致变色层,和离子液体(HMIM[TFSI])作为电解质。ECD能够在仅0.78±0.07s的持续时间内在短时间内降低其红外发射率（Δε=0.23）（导致红外温度从50下降到44°C），同时在3s内将其颜色从绿色变为黄色施加4V的正电压。此外,它表现出优异的灵活性，即使在弯曲条件下。这种简化的结构为可穿戴自适应伪装和多光谱显示器等应用提供了机会。
