柔性电致变色器件研究进展

Progress in Flexible Electrochromic Devices

电致变色材料是一类重要的光电功能材料,可以随周期性调整的电压改变颜色。这种可控的光学吸收率和透过率的调制在智能窗户、电致变色显示和防眩光后视镜等应用场合大显身手。近年来电致变色技术发展迅速,但当前的研究大多集中在传统刚性电致变色器件,通常以氧化铟锡(ITO)等导电玻璃为基底。这些刚性变色器件存在厚度大、共型性差、机械强度低、成本高等不可忽视的问题,阻碍了电致变色技术及其商业化的发展。伴随着开发可穿戴设备和电子皮肤等其他未来技术的热潮,柔性电致变色器件因其可折叠性、可穿戴性甚至可嵌入性而备受关注,已跻身成为电致变色领域的研究热点。本综述从制备柔性电致变色器件的材料出发,系统地概述了无机、有机、无机/有机复合及其他新型柔性电致变色器件最新进展和趋势,着重介绍了可拉伸电致变色器件的国内外研究进展。同时讨论了现阶段柔性电致变色器件在性能提升和实际应用等方面遇到的挑战,以及国内外研究者采取的应对措施。最后明确了柔性电致变色器件制备与提升性能的关键,并对未来的发展趋势做出展望。

Electrochromic materials with ability of changing color in response to periodically adjusted bias are an important class of optoelectric functional materials.The controllable modulation of light absorption and transmission can make a great contribution in applications such as smart windows,electrochromic displays and antiglare rear-view mirrors.In recent years,electrochromic technology has developed rapidly.However,the research so far mainly focuses on the traditional rigid electrochromic devices(ECD),mostly based on transparent conductive glass such as indium tin oxide(ITO)glass.The rigid electrochromic devices have some noticeable problems such as large thickness,poor conformability,low mechanical strength,high cost,etc.,which hinder their further development of electrochromic technology and their forward commercialization.With the upsurge of developing flexible devices that can be used in wearable devices and e-skin,flexible electrochromic devices(FECD)have attracted extensive attention due to their possibility of foldability,wearability and even embeddability,and have become a research hotspot in the electrochromic field.Starting from the materials for preparing FECD,this review systematically summarizes the recent progress and trend of flexible electrochromic devices based on inorganic,organic,inorganic/organic composite and other new materials.The review also focuses on the research progress of up to date stretchable electrochromic devices.At the same time,challenges in performance improvement and practical application of flexible electrochromic devices at the present stage as well as the corresponding measures taken in the literatures are discussed.Finally,the key to the preparation and performance improvement of flexible electrochromic devices is defined,and the future development trend is prospected.