变色龙仿生光子晶体智能材料的构筑、调控与耦合

The program is to construct a chameleon-like smarter film with photonic crystal structure, which can automatically feel the environmental change in temperature and incident light by tuning the structure color and coupling the metal nanoparticles. To select suitable photo-thermal sensitive polymers, the research will firstly studies the impact of the Lower Critical Solution Temperature of polymer on its sensitivity responding to temperature and incident light, and then constructs the photo-thermal sensitive polymeric film with photonic crystal structure. Furthermore, the research will tries to tune the relationship of the film structure color corresponding to the environmental temperature and the wave length of incident light, explores the coupling of the photonic crystal with the local surface plasmon resonance of metal nanoparticles, and demonstrates the film responding to all of the infrared, visible and ultraviolet light, meanwhile, enhances the responding sensitivity of film to temperature and incident light. Based on the study above, the research will reveals the regulations among the polymeric conformation, the polymer wettability and the structure color, establishes one to one correspondence among environment condition (wave length/temperature), polymeric wettability and structure color, thus to lay a solid theoretic foundation for the application of chameleon-like smarter materials with photonic crystal structure in new sensors, camouflage and stealth, communication and so on.

本项目拟构筑一种像变色龙一样的光子晶体智能薄膜，通过对材料结构色的调控和与纳米金属的耦合，实现薄膜对周围环境温度、辐照光波长变化的主动感知。通过选择合适的光热敏感聚合物，研究其临界相转变温度（LCST）对光热响应灵敏性的影响，构筑光子晶体光热敏感聚合物薄膜。调控薄膜结构色与环境温度、辐照光波长的对应关系和变化规律，探索光子晶体与纳米金属的局域表面等离子体共振（LSPR）耦合，实现材料对红外、可见光、紫外的全光谱响应，同时增强材料对光热响应的敏感性。在此基础上，揭示聚合物构像的变化与材料浸润性及光子晶体结构色之间的变化规律，建立环境条件（波长/ 温度）—聚合物浸润性—结构色之间一一对应的关系，从而为变色龙仿生光子晶体智能材料在新型传感器、军事伪装隐身及信息通讯等领域的实际应用打下理论基础。

光子晶体具有光带隙，在新型光学器件、光通讯等领域具有重要的研究价值。将光子晶体与刺激响应性聚合物结合在一起，可以构筑成灵敏度高、响应迅速以及颜色可变的响应性光子晶体，其在智能传感器、信号转化等领域均存在着广阔的应用前景。目前，对于光子晶体聚合物的研究已经实现了对部分物理化学刺激信号的比色响应。然而，由于聚合物本身性质以及响应灵敏度的限制，响应性光子晶体聚合物仍然存在着刺激目标有限以及响应性能较差等问题。本研究通过把纳米贵金属与响应性光子晶体共聚的方法，将纳米贵金属优异的光热性能，以及局域表面等离子体共振效应等特性与光子晶体的响应性耦合，最终达到提高响应性光子晶体对温度以及光照的响应特性的目的。此外还研究了将纳米贵金属与温度-电场响应性光子晶体结合(AuNPs@PNPVA,AgNPs@PNPVA)。在电场刺激引发薄膜比色响应的同时，还利用纳米贵金属的LSPR效应，激发了薄膜的光电流，实现了薄膜光信号和电信号之间的可逆转化。响应性光子晶体与纳米贵金属功能材料的复合，不仅改善了材料的响应特性，还实现了新的响应模式，即通过电流实现对光照响应，为构筑新型有机半导体二极管提供了新的思路和方法。