近日，安徽大学Zhijia Hu团队报道了丝网印刷胆甾液晶弹性体的动态防伪和可调谐激光。相关论文于2026年3月19日发表在《美国科学院院刊》杂志上。

结构色因其高稳定性、环境友好性及动态光学响应潜力，在防伪、显示和智能涂层等领域具有重要应用价值。然而，传统的光子晶体制备策略——如光刻和喷墨打印——存在诸多局限，包括掩模成本高、喷嘴易堵塞、晶格缺陷以及难以规模化生产等问题。

研究组引入创新的丝网印刷技术，基于胆甾相液晶弹性体实现了高保真、多色结构色图案的制备，攻克了介观螺旋结构取向调控及光子带隙空间均匀性控制的关键难题。该研究揭示了胆甾相液晶弹性体的手性螺旋超结构在决定反射光圆偏振特性中的关键作用。所印刷图案展现出动态光学行为，包括视角相关的色移效应、由螺旋手性决定的本征选择性圆偏振反射，以及应变下的可逆力致变色响应。

此外，通过整合光致变色螺吡喃，该材料在光热刺激下实现了多刺激响应的颜色与荧光切换，并获得了紫外可调谐（645–685 nm）的随机激光发射。该研究表明，丝网印刷胆甾相液晶弹性体凭借其优异的基底兼容性与可扩展性，为下一代防伪标签、智能包装及柔性光子器件构建了极具前景的平台。

附：英文原文

Title: Dynamic anticounterfeiting and tunable lasing with screen-printed cholesteric liquid crystal elastomers

Author: Qu, Guangyin, Guo, Lulu, Zhang, Xiaojuan, Li, Siqi, Kuai, Yan, Fu, Weiwei, Yang, Tianyu, Wen, Jialin, Yu, Benli, Hu, Zhijia

Issue&Volume: 2026-3-19

Abstract: Structural colors hold significant application value in anticounterfeiting, displays, and smart coatings due to their high stability, eco-friendliness, and dynamic optical response potential. However, conventional fabrication strategies for photonic crystals—such as photolithography and inkjet printing—suffer from limitations including high mask costs, nozzle clogging, lattice defects, and difficulties in scaling production. This study introduces an innovative screen-printing technique to achieve high-fidelity and multicolor structural color patterning based on cholesteric liquid crystal elastomers (CLCEs), overcoming key challenges in controlling the alignment of mesoscopic helical structures and ensuring spatial homogeneity of the photonic bandgap. Crucially, the chiral helical superstructure of CLCEs was investigated, revealing its decisive role in governing the circular polarization properties of the reflected light. The printed patterns exhibit dynamic optical behaviors, including viewing-angle-dependent color shifts, inherent selective circularly polarized reflection dictated by the handedness of the helix, and reversible mechanochromic responses under strain. Furthermore, integration of photochromic spiropyran enables multistimulus-responsive color and fluorescence switching under light and thermal stimuli, as well as ultraviolet-tunable (645 to 685 nm) random lasing emission. This work demonstrates that screen-printed CLCEs, with their excellent substrate compatibility and scalability, constitute a promising platform for next-generation anticounterfeiting labels, smart packaging, and flexible photonic devices.

DOI: 10.1073/pnas.2535645123

Source: https://www.pnas.org/doi/abs/10.1073/pnas.2535645123