Abstract In this work, a smart electrochromic-supercapacitor device was designed and fabricated by employing a porous Co doped NiO film as positive electrode. The porous Co doped NiO film was obtained through a simple hydrothermal method. The areal specific capacitance of the prepared porous Co doped NiO film composites is 88.24 mF cm-2 and the color of films change from brown (colored) to yellow (bleached). Large planer spacing, porosity and high surface area of Co doped NiO guarantee achievement of high electrochemical and electrochromic performance. The constructed device has a high specific capacitance (10.8 mF cm-2), high energy density (3.84×10-3 mW h cm-2) and superior cycle stability (initial capacitance retention rate of 84.5% after 2000 charge/discharge cycles). After charging, two devices could light up two LED. Furthermore, the energy storage state of could be monitored by the color change of the device thus an intelligent electrochromic supercapacitor can be realized

中文翻译：

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基于多孔 Co 掺杂 NiO 薄膜的可视化电致变色-超级电容器装置

摘要 在这项工作中，以多孔 Co 掺杂 NiO 薄膜为正极，设计并制造了一种智能电致变色-超级电容器装置。通过简单的水热法获得了多孔Co掺杂NiO薄膜。制备的多孔Co掺杂NiO薄膜复合材料的面积比电容为88.24 mF cm-2，薄膜颜色从棕色（有色）变为黄色（漂白）。Co掺杂NiO的大平面间距、孔隙率和高表面积保证了高电化学和电致变色性能的实现。构建的器件具有高比电容（10.8 mF cm-2）、高能量密度（3.84×10-3 mW h cm-2）和优异的循环稳定性（2000次充放电循环后初始电容保持率为84.5%） . 充电后，两个设备可以点亮两个 LED。此外，