近日，北京化工大学的郭金宝与东南大学的李全等人合作并取得一项新进展。经过不懈努力，他们对量子点遇到蓝相液晶弹性体时的可视化全彩，和机械可切换圆偏振发光进行了研究。相关研究成果已于2024年6月14日在国际知名学术期刊《光：科学与应用》上发表。

聚合物基圆偏振发光（CPL）材料因其结构多样性、简易的制备过程、卓越的热稳定性以及可调的性能而受到广泛关注。然而，由于手性结构的调整难度，对聚合物基材料的CPL进行精细调控仍是一项挑战。在此，研究人员通过将红、绿、蓝量子点(QDs)掺杂到可重构的蓝相液晶弹性体(BPLCEs)中，实现了可视化的全彩CPL。

与胆甾型液晶弹性体(CLCEs)中观察到的CPL信号相反，BPLCEs的手性三维立方上层结构诱导了相反的CPL信号。值得注意的是，这种效应完全独立于光子带隙(PBGs)，即使PBGs与量子点的发射带之间没有匹配，也会产生高的glum值。同时，BPLCEs的晶格结构可以通过机械拉伸力实现可逆转换，进而控制CPL信号的开关。

更令人兴奋的是，这种变化可以通过BPLCEs中的动态二硫键进一步固定。此外，研究人员利用BPLCEs构建的防伪和信息加密智能聚合物基CPL系统，充分证明了基于BPLCEs的CPL活性材料在防伪、信息加密等领域的巨大潜力。

附：英文原文

Title: When quantum dots meet blue phase liquid crystal elastomers: visualized full-color and mechanically-switchable circularly polarized luminescence

Author: Li, Shan, Tang, Yuqi, Fan, Qingyan, Li, Ziyuan, Zhang, Xinfang, Wang, Jingxia, Guo, Jinbao, Li, Quan

Issue&Volume: 2024-06-14

Abstract: Polymer-based circularly polarized luminescence (CPL) materials with the advantage of diversified structure, easy fabrication, high thermal stability, and tunable properties have garnered considerable attention. However, adequate and precise tuning over CPL in polymer-based materials remains challenging due to the difficulty in regulating chiral structures. Herein, visualized full-color CPL is achieved by doping red, green, and blue quantum dots (QDs) into reconfigurable blue phase liquid crystal elastomers (BPLCEs). In contrast to the CPL signal observed in cholesteric liquid crystal elastomers (CLCEs), the chiral 3D cubic superstructure of BPLCEs induces an opposite CPL signal. Notably, this effect is entirely independent of photonic bandgaps (PBGs) and results in a high glum value, even without matching between PBGs and the emission bands of QDs. Meanwhile, the lattice structure of the BPLCEs can be reversibly switched via mechanical stretching force, inducing on-off switching of the CPL signals, and these variations can be further fixed using dynamic disulfide bonds in the BPLCEs. Moreover, the smart polymer-based CPL systems using the BPLCEs for anti-counterfeiting and information encryption have been demonstrated, suggesting the great potential of the BPLCEs-based CPL active materials.

DOI: 10.1038/s41377-024-01479-1

Source: https://www.nature.com/articles/s41377-024-01479-1