易斯酸添加的狭窄带间隙合聚合物的聚合物
Gregory C Welch1, Guillermo C Bazan
1Center for Polymers and Organic Solids, Department of Chemistry and Biochemistry, The University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|March 8, 2011
概括
易斯酸与结合式共聚物相互作用,修改后的受体单元增强结合. 这一策略创造了新的近红外吸收聚合物,具有可调节的带间隙.
科学领域:
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
- 摄影化学的使用.
背景情况:
- 结合性共聚物与供体和受体单位对于有机电子非常重要.
- 易斯酸相互作用可以调整这些材料的电子特性.
- 在佐[2,1,3]提亚醇 (BT) 单位中,固体阻碍会影响易斯酸的结合.
研究的目的:
- 为了研究易斯酸与窄带间隙联共聚物的相互作用.
- 了解接受器单元中的结构修改如何影响易斯酸协调.
- 通过易斯酸结合,探索创建新的近红外 (NIR) 吸收聚合物.
主要方法:
- 模型化合物和聚合物系统的合成和表征.
- 谱学研究包括紫外线光发射谱学 (UPS).
- 密度函数理论 (DFT) 计算分析电子结构变化.
主要成果:
- 聚合物1与小分子相比,由于BT位周围的固体阻碍,与B的结合较弱.
- 将pyridal[2,1,3]thiadiazole (PT) 与更基本的位相结合,增强了易斯酸的结合.
- 新的NIR吸收聚合物产生了带间隔可调节从1.31到0.89eV在BC6F53) 结合.
- 对PT的协调降低了HOMO和LUMO,而LUMO的降低更大,缩小了带间隙.
结论:
- 在BT单元中的立体阻碍降低了联共聚物中的易斯酸协调.
- 设计具有更基本位的受体单元,如PT,加强易斯酸相互作用.
- 易斯酸结合为先进的电子应用提供了一条可行的途径,用于设计具有可调节带间隙的NIR吸收聚合物.
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