CAREER: Developing n-type low bandgap conjugated macromolecules based on aza-dipyrromethene

在这个由凯斯西储大学化学系大分子、超分子和纳米化学项目资助的项目中，Genevieve Sauve将合成n型、低带隙共轭大分子。该方法是使用氮杂-二吡咯亚甲基（aza-DIPY）染料作为共聚单体构建单元，因为氮杂-DIPY是红色吸收剂并且具有高电子亲和力;它们的电子性质也应该通过取代基的变化和金属离子的螯合来调节。将合成氮杂-DIPY共聚单体并用于制备具有芳基-双炔基或芳基-双烯基单元的交替共聚物。 将确定聚合物的光电性能，然后通过将所选择的共轭聚合物与给电子聚合物如聚（3-己基噻吩）共混将其集成到聚合物太阳能电池中。 为了指导共混物的纳米级相分离，将合成用氮杂-DIPY基分子末端官能化的聚（3-己基噻吩）并用作共混剂。将分析薄膜形态，并将其与共混物组成和器件性能相关联。该计划的教育计划和更广泛的影响包括：1）在课堂和实验室教学任务中实施主动学习策略，并将太阳能转换主题纳入本科生和研究生课程; 2）指导和准备本科生和研究生进行尖端的多学科研究;（3）成为学习理工科的女学生的榜样和导师。由导电塑料制成的太阳能电池在技术上很有前途，但转换效率低，加工过程中无法再现。 这项研究旨在通过提高我们对如何合成新的有机聚合物来捕获光并有效地将其转化为电能的基本理解来解决其中的一些问题。 这种聚合物还可能在轻质、柔性有机电子和显示技术中找到应用。

In this project funded by the Macromolecular, Supramolecular and Nanochemistry Program of the Chemistry Division, Genevieve Sauve of Case Western Reserve University will synthesize n-type, low bandgap conjugated macromolecules. The approach is to use aza-dipyrromethene (aza-DIPY) dyes as a comonomer building block, because aza-DIPYs are red-absorbers and have high electron affinities; their electronic properties also should be tunable via changes in substituents and chelation of metal ions. The aza-DIPY comonomers will be synthesized and used to preprare alternating copolymers with aryl-bis-alkynyl or aryl-bis-alkenyl units. The opto-electronic properties of the polymers will be determined, and then selected conjugated polymers will be integrated into polymer solar cells by blending them with electron-donating polymers such as poly(3-hexylthiophene). To direct nanoscale phase separation of the blend, poly(3-hexylthiophene) end-functionalized with aza-DIPY-based molecules will be synthesized and used as blending agents. Film morphologies will be analyzed and correlated with blend composition and device performance. The education plan and broader impacts of this program include: 1) implementing active-learning strategies in classroom and laboratory teaching assignments as well as incorporating solar energy conversion topics into the undergraduate and graduate curriculum; 2) mentoring and preparing undergraduate and graduate students to undertake cutting edge multidisciplinary research; and 3) serving as a role model and mentor for women students studying science and engineering.Solar cells made from electrically conducting plastics are technologically promising but suffer from low conversion efficiencies and irreproducibility in processing. This research seeks to address some of those issues by enhancing our fundamental understanding of how to synthesize new organic polymers to capture light and efficiently turn it into electrical energy. The polymers might also find application in lightweight, flexible organic electronics and display technologies.