Jeong Chan Yang, Kubota Takashi, Tajima Kazuki
National Institute of Advanced Industrial Science and Technology (AIST) 1-1-1 Higashi Tsukuba Ibaraki 305-8565 Japan
Kitami Institute of Technology (KIT) 165 Koen-cho Kitami Hokkaido 090-8507 Japan.
RSC Adv. 2021 Aug 24;11(46):28614-28620. doi: 10.1039/d1ra05280b. eCollection 2021 Aug 23.
Smart windows, which control the amount of light entering buildings, houses, and automobiles, are promising in terms of energy conservation and their low environmental impact. Particularly, a next-generation smart window for automobiles will require high optical modulation, along with flexibility to adapt to various intelligent designs. We have previously fabricated electrochromic devices (ECDs) by wet coating glass substrates with nanoparticles (NPs), such as water-dispersive ink containing tungsten oxide (WO), and Prussian blue (PB), and have evaluated and confirmed the various electrochromic (EC) properties, such as optical modulation, cyclic durability, and colouration efficiency, of the ECDs. However, glass substrates are heavy and difficult to adapt by deformation to meet the demand of next-generation automobiles. In this study, we aim to prepare complementary ECDs by wet coating WO and PB thin films on indium tin oxide (ITO)-coated flexible polyethylene terephthalate (PET) substrates. Chromaticity and haze of ECDs were investigated in detail as evaluation indexes to verify specifications for practical use in automotive applications. Repeated switching, bending, and twisting did not degrade the ECD properties, thereby demonstrating its durability and mechanical robustness. These excellent electrochromic properties of the flexible ECDs suggest that they are promising materials for application in next-generation smart windows for automobiles.
智能窗户能够控制进入建筑物、房屋和汽车的光线量，在节能和低环境影响方面具有广阔前景。特别是，下一代汽车智能窗户除了需要具备适应各种智能设计的灵活性外，还需要高光学调制能力。我们之前通过在玻璃基板上湿法涂覆纳米颗粒（NPs）来制备电致变色器件（ECD），例如含有氧化钨（WO）和普鲁士蓝（PB）的水分散性墨水，并评估和确认了ECD的各种电致变色（EC）特性，如光学调制、循环耐久性和着色效率。然而，玻璃基板很重，难以通过变形来适应下一代汽车的需求。在本研究中，我们旨在通过在涂有氧化铟锡（ITO）的柔性聚对苯二甲酸乙二酯（PET）基板上湿法涂覆WO和PB薄膜来制备互补ECD。详细研究了ECD的色度和雾度，作为评估指标以验证其在汽车应用中的实际使用规格。反复的开关、弯曲和扭转并没有降低ECD的性能，从而证明了其耐久性和机械坚固性。柔性ECD的这些优异电致变色特性表明它们是下一代汽车智能窗户应用的有前途的材料。
