CAREER: Device Engineering for High-Performance Polymer Bulk Heterojunction Solar Cells

研究目标和方法：本研究的目的是解决与聚合物太阳能电池的效率和可靠性有关的一些主要问题，并丰富目前对聚合物光伏电池基本结构-性能关系的理解。该方法是利用嵌段共聚物的聚合物刷状结构在横向和垂直方向上设计活性层形态。智力优势：通过纳米畴预图像化和聚合物刷状生长的控制形态，将构建复合双层结构，以促进激子解离和电荷传输。下层的聚合物刷层为空穴传输提供了直接途径，而上层由嵌段共聚物介导的供体-受体共混层为有效的激子解离和收获保持了较大的界面面积。此外，增强的结晶度和优化的垂直组成剖面有利于电荷的传输和收集。将系统地研究基本的结构-性能关系，如聚合物刷状和嵌段共聚物的链构象和填充如何影响效率和热稳定性。更广泛的影响：这个CAREER项目展示了跨学科研究和教育的协同整合。其结果将通过实施多学科教育和推广计划影响社会。它将为研究生和本科生提供大量的多学科培训，这对他们未来职业生涯的成功至关重要。7 -12年级少数民族学生的外展将通过PI完成。在该项目中，PI开发纳米技术和太阳能的科学模块，并为阿拉巴马州的中学教师提供培训。

Research Objectives and Approaches:The objective of this research is to address some major issues of polymer solar cells related to the efficiency and reliability, and enrich current understanding of the fundamental structure-property relationships involved in polymer photovoltaics. The approach is to engineer active layer morphology in both lateral and vertical directions using polymer brush structure with incorporation of block copolymer.Intellectual Merit: With controlled morphology from nanodomain pre-patterning followed by polymer brush growth, a composite bilayer structure will be built to facilitate both exciton dissociation and charge transport. The polymer brushes in the down layer provide direct pathways for hole transport, while the up donor-acceptor blend layer mediated by block copolymer keeps the large interfacial area for efficient exciton dissociation and harvesting. Moreover, the enhanced crystallinity and optimized vertical composition profile facilitate charge transport and collection. The fundamental structure-property relationships, such as how chain conformation and packing from polymer brush and block copolymer affect efficiency and thermal stability, will be systematically studied.Broader Impact:This CAREER project presents synergistic integration of interdisciplinary research and education. The outcome will impact society by implementing multidisciplinary education and outreach programs. It will provide graduate and undergraduate students with substantial multidisciplinary trainings which are essential for success in their future careers. The outreach to 7th-12th grade minority students will be accomplished through the PI?s participation in Alabama Black Belt program, in which the PI develops scientific modules on nanotechnology and solar energy and provides trainings for teachers from secondary schools in Alabama.