基于超分子凝胶的自组装在提高材料电光活性与稳定性方面的研究

Organic electro-optic (EO) materials have attracted considerable attention over the past two decades because of their large EO coefficients, ultrafast response times, and easy processing, and have shown great potential applications in optical communication and optical data processing technologies. However, for practical applications, the main challenges in preparing excellent EO materials were that: 1) Translate the first-order hyperpolarizability (β) to the macroscopic electro-optic (EO) coefficients (r33) of the materials effectively; 2) Promote the long-term stability of the materials. To overcome these challenges, this project aims to take advantage of the supramolecular gel system instead of traditional host-guest doping system. This new system can design chromophores to non-centrosymmetric head-to-head arrangement without any additional external mediation. It can display spontaneous second harmonic generation, thus may also enhance the macroscopic EO activity and meanwhile promote excellent long-term alignment stability. This will be the most promising material. This project will aim to calculation and design high-performance chromophores through the EO activity growth mechanism. We prepare a series of supramolecular gels and explore the influence of the structures of chromophores and gelator, the interaction between chromophores on EO coefficient in this new system. The final purpose of this project is to reveal the internal reason of high EO activity also excellent long-term alignment stability of this new system and prepared new materials with excellent properties. The new model will be proposed and will provide theoretical and technical basis for exploring the new organic EO materials and devices.

有机电光材料以电光系数大﹑响应速度快﹑易于加工等优势成为研究热点，在光通信和光存储领域有巨大的潜在应用。目前有机电光材料碰到的主要瓶颈是有机分子间强的偶极相互作用导致微观一阶分子超极化率(β)不能有效转换成宏观电光系数(r33)，而且电光系数与取向稳定性不能同时达到最优。针对这一难题，本项目提出设计新颖的具有自组装效应的有机超分子凝胶体系代替传统的主客体掺杂体系，此种新体系不需要借助外力诱导，能实现发色团分子的自发定向排列，电光系数值高且取向稳定性好，有望成为最有潜力的实用性材料。本项目拟通过探索材料的宏观电光系数增长原理进行微观理论计算以及高性能发色团的合成；制备有机超分子凝胶体系，研究发色团结构、凝胶因子以及发色团与发色团之间的相互作用等对体系的影响，揭示有机超分子凝胶体系电光系数高且取向稳定性好的内在原因；制备出高电光活性、高取向稳定性的电光材料。

本课题通过引入具有自组装效应的有机超分子凝胶体系代替传统的主客体掺杂体系来提高材料的电光活性与稳定性。通过合成高性能发色团，包括双给体发色团，电子桥上修饰的发色团，探究了引入不同的位阻基团以及位阻基团的空间大小，电子桥连接方式等对材料电光性能的影响，探索材料的宏观电光系数增长原理；制备了有机超分子凝胶体系，研究发色团结构、凝胶因子以及发色团与发色团之间的相互作用等对体系的影响。基本完成研究目标。另外，我们还拓宽了有机光学发色团的应用领域，在紫外打印和防伪领域进行了探索，制备了一系列具有化学稳定性和光学稳定性的发色团并制备成了优异的光学薄膜，表现出对光刺激与机械刺激的快速响应、高可逆性和高对比度特性，在多级防伪材料和加密纸张中具备一定的应用前景。项目资助发表SCI论文10篇，待发表3篇。参与国内学术会议2次，培养硕士生9名，其中2名将于2022.6取得硕士学位，7名在读。培养本科生21人，其中已经顺利毕业10人，其中2人进入东华大学深造，1人进入武汉理工大学深造。投入经费26万元，支出18.67万元，各项支出基本与预算相符。剩余经费7.33万元，剩余经费计划用于本课题研究后续支出。