CAREER:Increasing charge separation and extraction by ferroelectric polymer induced persisting electric-field for efficient organic solar cells

研究目标和方法本研究的目标是通过消除主要的能量损失通道，将有机光伏器件的效率提高到15%以上。该方法是在有机/电极界面处应用超薄铁电层，在有机半导体层中诱导强电场，以实现有效的电荷分离和提取。有了这种独特的结构，就不需要施加外场来保持电场诱导的电荷提取。该项目提供了一种变革性的设备设计，有望将有机光伏设备的效率提高到热力学极限。铁电聚合物是一种通用的双功能界面层，可用于低功和高功的表面修饰。此外，该研究将为有机光伏器件中电荷光的产生、收集和开路电压的起源的物理学带来新的基本见解。更广泛的影响关于强电场对电荷解离和提取的影响的新的基本认识将为电场控制电子器件的新应用建立理论基础，包括有机发光二极管、激子太阳能电池、高速光折变聚合物、有机双稳态存储器、有机光电探测器、有机晶体管和多铁性材料。这项研究将为不同年龄、性别和种族的学生提供支持。这个学习平台，特别针对高中学生，将鼓励学生考虑在能源转换工程领域的职业生涯，并为PI提供必要的经验，以发展成为一名优秀的教师学者。

Research Objectives and ApproachesThe objective of this research is to boost the efficiency of organic photovoltaic devices to over 15% by eliminating the major energy loss channels. The approach is to apply an ultrathin ferroelectric layer at the organic/electrode interface to induce a strong electric field into the organic semiconductor layer for efficient charge separation and extraction. With this unique structure, there will be no need to apply an external field to have the electric-field-induced charge extraction persist. Intellectual MeritThis project provides a transformative device design that promises to increase the efficiency of organic photovoltaic devices potentially to the thermodynamic limit. The ferroelectric polymer is a universal dual function interfacial layer for both low- and high-work function surface modifications. Further, this research will bring new fundamental insight to the physics of charge photo-generation, collection, and the origin of the open circuit voltage in organic photovoltaic devices. Broader ImpactsNew fundamental understanding regarding the influence of a strong electric field on charge dissociation and extraction will establish the theoretical base for new applications in electric field-controlled electronic devices, including organic light emitting diodes, excitonic solar cells, high speed photorefractive polymers, organic bistable memory, organic photodetectors, organic transistors, and multiferroics. This research will support outreach activities for students diversified in age, gender, and ethnicity. This platform of learning, which particularly targets high school students, will encourage students to consider careers in the energy conversion engineering field and provide the PI the experience necessary to develop into a stellar teacher-scholar.