Electrochromic (EC) device reversibly changes color and optical state by applying electric potential. EC materials shows color change due to redox process and electron transfer across various states under influence of electric field. EC devices are categorized based on various classes of EC materials inorganic metal oxide and polyoxometalates (POMs), metal complexes, hybrid materials, metal plasmonics–metal/alloy and organic molecules/conjugated polymers. EC materials and its viability for device application are presented herein considering various performance parameter indices. The performance of EC devices is monitored by its switching time between transparent‐bleached state to colored state and vice versa, cycling stability, coloration efficiency, applied voltage, electro‐optical properties, electrochemical stability and breakdown potentials of EC materials and electrolytes. Recent advances in the area of EC devices and materials, its operation mechanism in various categories of EC materials along with existing challenges and recommendations to improve performances and reliability are summarized.

中文翻译：

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电致变色器件的最新进展综述：一种材料方法

电致变色（EC）设备通过施加电势可逆地更改颜色和光学状态。EC材料在电场的作用下由于氧化还原过程和电子在各种状态下的转移而显示出颜色变化。EC设备的分类基于各种EC材料，包括无机金属氧化物和多金属氧酸盐（POM），金属络合物，杂化材料，金属等离子-金属/合金和有机分子/共轭聚合物。考虑到各种性能参数指标，本文介绍了EC材料及其在设备应用中的可行性。EC器件的性能通过其在透明漂白状态到有色状态之间的切换时间（反之亦然），循环稳定性，着色效率，施加电压，电光特性，EC材料和电解质的电化学稳定性和击穿电位。总结了EC器件和材料领域的最新进展，其在各种EC材料中的运行机制以及现有的挑战和改善性能和可靠性的建议。