SOLAR: Development Methods to Predict Phase Separation and Charge Transport in Bulk Heterojunction Conjugated Polymer Solar Cells

技术综述：最重要的科学挑战之一是如何有效地收集、转换、储存和利用太阳能。近年来，人们对开发太阳能电池用有机材料的兴趣与日俱增。有机太阳能电池为室内和室外应用提供了一种低成本、大面积、灵活、重量轻、清洁和安静的替代能源。然而，必须提高它们的电力转换效率和运行寿命，以实现大规模商业化和实施，并产生深远的社会影响。因此，迫切需要了解这些设备中的基本过程。目前，新材料的合成和优化费时费力，且依赖于试错法，成功率较低。因此，迫切需要从材料的化学成分和块体形貌来合理地预测材料的性能，以加速技术的发展，并离开经验优化。这一跨学科计划的目标是融合化学、材料、物理和数学方面的互补专业知识，在有机太阳能电池的科学和技术方面取得突破。该团队将致力于：1)开发模拟BHJ太阳能电池相分离的新方法；2)开发预测有机半导体中载流子迁移率的第一性原理方法；3)对施主-受主互穿网络的纳米尺度表征；4)对电荷产生和传输过程的理解；5)在理论预测的指导下合成新型共轭聚合物；6)评估材料性能。模拟方法将在经过充分研究的材料上得到广泛验证，然后将被用于设计更高效的新材料。作为精心安排的理论和实验工作，该项目努力实现高效和低成本有机太阳能电池发展的变革性突破。非技术摘要：预计到2050年，世界能源需求将翻一番。到目前为止，在不向环境排放二氧化碳的情况下，没有可行的技术来应对这一挑战。有鉴于此，提高塑料太阳能电池的功率转换效率和运行寿命为创造一种具有广泛应用前景的清洁和潜在经济可行的能源提供了机会。这项拟议研究的目标是组建一支在化学、材料、物理和数学方面具有互补专业知识的科学家团队，为合理开发材料和太阳能电池器件结构建立理论指导方针。该计划的成功完成预计将缓解目前通过试错程序优化设备性能的需求，并将为加速技术创新铺平道路。该项目通过本科生和研究生以及博士后研究人员的参与，将跨学科研究和教育结合在一起，特别强调招收代表性不足的学生。UCSB将开设关于有机半导体及其在能源转换中的应用的新课程。这些课程将在跨学科的环境中教授，研究人员希望在这种环境下解决在可再生能源领域培训研究人员的迫切需求。此外，还将为当地学校的K-12学生、教师和家长举办关于太阳能的讲习班和演示，以提高对可再生和可持续能源的认识。此外，通过让学生在这么早的阶段接触到这些想法，研究人员希望唤醒他们追求科学事业的愿望。

TECHNICAL SUMMARY:One of the most important scientific challenges is how to efficiently harvest, convert, store and utilize solar energy. In recent years, there has been a growing interest of developing organic materials for solar cell applications. Organic solar cells offer a low-cost, large-area, flexible, light-weight, clean, and quiet alternative energy source for both indoor and outdoor applications. However, their power conversion efficiencies and operational lifetimes must be improved to enable large-scale commercialization and implementation and deep societal impact. Thus, there is an urgent need to understand fundamental processes in these devices. Currently, the synthesis and optimization of new materials is time consuming and labor intensive, and relies on trial and error approaches with poor success rates. There is therefore a great need to rationally anticipate materials performance from their chemical composition and bulk morphology to accelerate technology development and depart from empirical optimization. The goal of this interdisciplinary program is to mesh complementary expertise in chemistry, materials, physics, and mathematics, to make breakthroughs in the science and technology of organic solar cells. The team will address: 1) the development of new methods to simulate phase separation in BHJ solar cells; 2) the development of first-principles methods to predict carrier mobilities in organic semiconductors; 3) the nanoscale characterization of donor-acceptor interpenetrating networks; 4) the understanding of charge generation and transport process; 5) the synthesis of new conjugated polymers guided by the theoretical predictions; 6) evaluation of materials performance. The simulation methods will be validated extensively on well-studied materials and will then be capitalized for the design of more efficient new materials. As well-orchestrated theoretical and experimental efforts, the project strives to achieve transformative breakthroughs for the development of high-efficiency and low-cost organic solar cells.NON-TECHNICAL SUMMARY: The world demand for energy is expected to double by 2050. As of now, there is no viable technology to address this challenge without emission of carbon dioxide to the environment. In view of this, increasing the power conversion efficiency and operational lifetime of plastic solar cells is provides the opportunity to create a clean and potentially economically viable energy source with a wide range of applications. The goal of the proposed research is to assemble the team of scientists with complementary expertise in chemistry, materials, physics, and mathematics, to establish theoretical guidelines for a rational development of materials and solar cell device structures. Successful completion of the program is expected to relieve the current need to optimize device performance via trial and error procedures and will pave the way for an acceleration of technical innovation. This project integrates interdisciplinary research and education by involving the participation of undergraduate and graduate students and postdoctoral researchers, with special emphasis in the recruitment of underrepresented students. New courses on organic semiconductors and their applications in energy conversion will be offered at UCSB. The courses will be taught in an interdisciplinary environment, with which the investigators hope to address the urgent need to train researchers in the area of renewable energies. Furthermore, Workshops and demonstrations on solar energy for K-12 students, teachers, and parents in local schools will be developed to create awareness about renewable and sustainable energy sources. In addition, by exposing students to these ideas at such an early stage, the investigators hope to awaken in them the desire to pursue a career in sciences.