新型双发色团二阶非线性光学材料的设计、合成与性能表征

Organic second-order nonlinear materials have been extensively studied because of their excellent properties, such as large electro-optic (EO) coefficient, ultrafast response time, and easy molecular design and processability, and have been used in the high performance optoelectronic devices. Microscopic first-order molecular hyperpolarizability cannot efficiently convert into the macroscopic electro-optic coefficient, because of the strong dipole-dipole interaction between organic electro-optic chromophores. This became the field of technical bottleneck. To solve this problem, the project proposes to take advantage of the binary-chromophore electro-optic polymer system instead of traditional single chromophore system. This system can effectively increase chromophore concentration, and electro-optic activity will be higher than the electro-optic coefficient of the sum of single chromophore systems. This will become the most promising material. The project will intend to study the design and calculation of high-performance binary-chromophore materials through the polarization efficiency growth mechanism. A series of binary-chromophore materials will be prepared, and study the influence of the guest and host chromophore type, the concentration, the composition, and the polymer environment on EO coefficient of the binary-chromophore materials, and look for the new rules. The new model will be proposed and give the conditions for high electro-optic activity and orientation stability binary-chromophore materials. This will provide theoretical and technical basis for exploring the new organic EO materials and devices.

有机二阶非线性光学材料以非线性光学系数大﹑响应速度快﹑易于进行分子设计与加工等优良性能成为研究热点，在高性能光电子器件等领域有广泛的应用。目前有机电光分子间强的偶极相互作用导致微观一阶分子超极化率不能有效地转换成宏观电光系数，成为该领域技术瓶颈。针对这一难题，本项目提出设计并合成新型双发色团聚合物电光材料（二元体系）来代替传统的单一发色团组份的材料，此种体系能够有效增加发色团含量，且电光系数比单一发色团体系电光系数的加和更高，成为最有希望的实用性材料。本项目拟通过研究材料极化效率增长机制进行高性能二元体系的设计及微观性能理论计算；制备系列二元体系，研究主客体发色团种类、浓度、组成以及聚合物环境等对体系电光系数的影响，寻找二元体系存在的新规律；建立新模型，并最终给出研制高电光活性、高取向稳定性二元电光材料的条件，为探索发展新型聚合物电光材料及器件提供理论与技术依据。

有机二阶非线性光学材料以非线性光学系数大﹑响应速度快﹑易于进行分子设计与加工等优良性能成为研究热点，在高性能光电子器件等领域有广泛的应用。本项目提出了新型双发色团聚合物电光材料（二元体系）来代替传统的单一发色团组份的材料，经过三年的时间，合成了一系列的主客体发色团材料。通过在二元体系中改变客体发色团与主体发色团的摩尔浓度比来探究主客体发色团的最佳摩尔比。与此同时还探究了主体发色团的种类，客体发色团的种类与聚合物主链的种类对最佳摩尔比的影响。最后发现这些因素对最佳摩尔比没有影响，所有的二元体系在为1:1时，其电光系数的增长率最高。几乎所有的二元体系都展现了其电光系数的提高，大大超过了其组分单独存在时的电光系数之和。同时从发色团的结构，紫外-可见-近红外吸收光谱以及密度泛函理论(DFT)计算等方面，通过不同二元体系在1:1时其电光系数增长率的不同来探究二元体系中主客体发色团的最佳选择。为探索发展新型聚合物电光材料及器件提供理论依据与物质基础。