变色龙皮肤表面周期性排列的鸟嘌呤纳米晶可以选择性反射可见光，使皮肤呈现虹彩结构色。当遇到危险或刺激时，变色龙通过改变皮肤拉伸率调整颗粒间距，实现皮肤结构色从红到蓝的快速转变，这种特殊的力致变色特性引起科研工作者广泛关注。设计制备具有明亮结构色和高灵敏度的人工仿生变色龙皮肤已成为胶体领域和光物理学领域的研究热点。研究发现，变色龙皮肤中相邻鸟嘌呤纳米晶之间的距离(D_s-s)和折射率对比度(Δn)对力致色变性能和结构色饱和度具有关键作用。然而，目前已报道的仿生变色龙皮肤具有较小的D_s-s和Δn，导致材料性能存在灵敏度低，结构色弱、稳定性差等问题。构建大D_s-s和Δn的非密堆积有序结构是制备高性能人工变色龙皮肤的前提，也是一项巨大挑战。

图 1 人工变色龙皮肤的仿生原理及合成示意图

  广东工业大学材能学院杨东朋副教授和黄少铭教授团队受变色龙结构启发，从构建非密堆积有序结构入手，基于SiO₂胶体颗粒在聚合物中非密堆积组装，通过改变聚合物折射率和SiO₂浓度分别调控Δn和D_s-s的策略，成功制备出灵敏度高和结构色明亮的人工变色龙皮肤（力致色变胶体晶）。制备的人工变色龙皮肤具有优异的力致变色性能，如波长调变范围大(Δλ = 205 nm)、灵敏度高(3.7 nm/%)、响应速度快(2.2 nm/ms)、稳定性好(>1年)和可逆性佳(>100次)等。由于具有高灵敏度，制备的力致色变胶体晶可以通过输出不同结构色报告蚯蚓蠕动过程中皮肤应变的变化。

图 2 人工变色龙皮肤用于自报告蚯蚓皮肤应变

  原文链接：https://pubs.acs.org/doi/pdf/10.1021/acsami.2c00561

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