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An intelligent light-managing ionic skin for UV-protection, IR stealth, and optical camouflaged Morse codes

“光调控”的智能水凝胶离子皮肤用于紫外线防护、 红外屏蔽和光学伪装的莫尔斯电码


Ionic skins that demonstrate great advantages in the mechanical properties and multiple sensory capabilities are regarded as an attractive candidate to mimic functions of human skin. However, human skin is vulnerable to be damaged under long-time sunlight irradiation, and most of the current ionic skins also lack a protection against harmful ultraviolet and infrared lights. Herein, this work develops a multifunctional ionic skin based on ionic conductive and light-managing hydrogels via a facile one-step locally confined polymerization. It is mechanically adaptable, able to modulate light in the broadband solar spectrum, and protect human skin from the harmful ultraviolet and infrared lights. Moreover, without complicated processing, the ionic skin enables human-machine interactions via wireless and optical camouflaged Morse codes. We believe this work will promote the development of smart wearable devices with multiple customizable functions.


由于广泛可调的机械性能和多重感应功能, 离子皮肤被认为是模拟人体皮肤功能的最具吸引力的候选材料. 然而, 目前报道的离子皮肤大多数缺乏对太阳光谱的管理能力以及对人体皮肤的光学保护作用. 特别是长期暴露在太阳光下的皮肤很容易被紫外线辐射和红外光引起的过热损伤. 本研究使用限域聚合的方法, 开发了一种温敏性的导电聚合物水凝胶离子皮肤. 这种离子皮肤无需复杂的制备技术, 不仅能够以国际莫尔斯电码的形式实现光学伪装的人机无线对话, 还可以对全太阳光范围内的光谱进行调控, 并具有强韧的机械性能. 我们相信, 该离子皮肤的设计灵感也将启发其他具有可定制功能的智能可穿戴器件的发展.


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This work was supported by the National Natural Science Foundation of China (51973035 and 51733003).

Author information




Author contributions Shi X, Wu P and Lei Z designed the experiments. Shi X performed the experiments and prepared the manuscript. Wu P and Lei Z supervised the project and revised the manuscript.

Corresponding authors

Correspondence to Zhouyue Lei or Peiyi Wu.

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Conflict of interest The authors declare that they have no conflict of interest.

Additional information

Xiaofang Shi received her PhD degree in polymer chemistry and physics under the supervision of Prof. Peiyi Wu at Fudan University (2021). Her research interest mainly focuses on the syntheses and application of multifunctional hydrogel materials.

Zhouyue Lei is a postdoctoral fellow at Harvard University. She received her PhD degree in polymer chemistry and physics under the supervision of Prof. Peiyi Wu at Fudan University (2019). Her research interest mainly focuses on soft ionic materials and their intelligent applications.

Peiyi Wu is a professor at the College of Chemistry, Chemical Engineering and Biotechnology, Donghua University (China) and a fellow of the Royal Society of Chemistry. He received his PhD degree at the University of Essen (Germany) in 1998. His research interests are focused on the 2D-IR spectroscopy, flexible hydrogel electronics and iontronics, and the synthesis and application of 2D materials.

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Shi, X., Lei, Z. & Wu, P. An intelligent light-managing ionic skin for UV-protection, IR stealth, and optical camouflaged Morse codes. Sci. China Mater. (2021).

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  • ionic skins
  • hydrogels
  • light-managing
  • human-machine interfaces