Tailoring Transport in Transparent and Conducting Non-conjugated Polymers for Next-Generation Materials in Organic Photovoltaic Devices

项目负责人：Boudouris， bryan提案编号：1336731机构：普渡大学标题：为下一代有机光伏器件材料量身定制透明和导电非共轭聚合物传输有机光伏（OPV）电池正在记录器件效率，由于材料设计的突破，该效率开始与许多无机光伏系统相媲美；因此，它们是可持续能源生产的潜在来源。然而，许多开创性的研究都集中在π共轭、光吸收大分子的设计上，用于OPV器件的半导体层。尽管需要有效地从太阳能电池中去除光产生的电荷，但在用于在OPV器件的电极-有机界面处提取电荷的新型聚合物材料领域取得的成功较少。因此，迫切需要开发和理解高度透明、在环境条件下稳定、能够快速传输电荷的新型材料中的基本电荷传输。在这里，PI介绍了一种有前途的新型导电聚合物，其中一个稳定的自由基基团悬垂在大分子链的每个重复单元上，其聚合物主链完全由脂肪碳碳键组成；这些材料被称为自由基聚合物。除了提供一种传导电荷的方法外，自由基聚合物还具有传统上与普通脂肪族聚合物（如聚苯乙烯）相关的优点，因为它们：1)可以由容易合成的单体生成，2)可以通过可控机制（如可控自由基聚合）进行大规模聚合，3)易于从溶液或熔体中加工。因此，预计该项目将能够生成透明、导电的聚合物薄膜，与传统的OPV电荷收集层(例如聚（3,4-乙烯二氧噻吩）-聚（苯乙烯磺酸盐）（PEDOT:PSS）相比，该薄膜具有独特的合成、加工和稳定性优势，同时仍保持高电荷转移率。自由基聚合物的分子结构与其固态光电性能之间的相互作用在基本结构-性能关系和OPV器件中的性能方面都是重要的。破译这些相互作用将需要聚合物合成、结构表征和电子测试的结合。这些技术的实现将导致：1)合成新的空穴导电和电子导电非共轭聚合物，2)描述自由基聚合物中的电荷传输，从而改善这些功能大分子的电导率值，以及3)这些材料在OPV器件中的利用，从而可以找到一种环境稳定、低成本的替代现有电荷收集层的方法。因此，研究目标的完成将为聚合物开发和有机电子界面修饰的新领域奠定基础，并对有机光伏和可持续能源领域产生深远影响。这可能会导致高性能的OPV设备，这将有助于解决当前全球能源格局的不确定性。此外，关于新型固态聚合物导体中电荷输运关系的基本发现将有可能扩展到目前由共轭材料主导的有机电子学的其他领域。除了提供对自由基聚合物导体的具体物理理解外，该项目还将通过实验室和外展活动帮助研究生，本科生和高中生的教学和职业发展。例如，它将通过支持布杜里斯创立的普渡项目SEED高中研究经验，增加传统上代表性不足的群体在科学和工程领域的参与。连接化学、聚合物科学、化学工程和电气工程等学科，将为与该项目相关的研究生、本科生和高中生提供一个独特的机会，参与跨学科、能源相关的研究，为他们未来在学术和工业领域的努力做好准备。研究和教育活动之间的这种协同关系对于产生高影响力的科学成果、产生变革性技术和激励下一代可持续能源科学家和工程师至关重要。

PI: Boudouris, BryanProposal Number: 1336731Institution: Purdue UniversityTitle: Tailoring Transport in Transparent and Conducting Non-conjugated Polymers for Next-Generation Materials in Organic Photovoltaic DevicesOrganic photovoltaic (OPV) cells are recording device efficiencies that are beginning to rival many inorganic photovoltaic systems due to breakthroughs in the design of materials; as such, they present themselves as potential sources of sustainable energy generation. However, much of the groundbreaking research has focused on the design of pi-conjugated, light-absorbing macromolecules for use in the semiconducting layers of the OPV devices. Less success has been had in the realm of new polymeric materials for charge extraction at the electrode-organic interfaces of OPV devices despite the inherent need to remove the photogenerated charges from the solar cell efficiently. Therefore, there exists a critical need to develop and understand the fundamental charge transport in novel materials that are highly transparent, stable in ambient conditions, and that have the ability to transport charges in a rapid manner. Here, the PI introduces a promising new class of conducting polymers where a stable radical group is pendant on each repeat unit of a macromolecular chain whose polymer backbone is composed entirely of aliphatic carbon-carbon bonds; these materials are known as radical polymers. In addition to providing a method by which to conduct charge, radical polymers have the advantages traditionally associated with common aliphatic polymers (e.g., polystyrene) in that they: 1) can be generated from easily-synthesized monomers, 2) have their polymerizations occur through controlled mechanisms (e.g., controlled radical polymerizations) and on large scales, and 3) are processed readily either from solution or from the melt. Therefore, it is anticipated that the project will be able to generate transparent, conducting polymer thin films that have distinct synthetic, processing, and stability advantages over traditional OPV charge-collecting layers [e.g., poly(3,4-ethylene dioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS)] while still retaining high charge transfer rates.The interplay between the molecular architectures of radical polymers and their solid state optoelectronic properties is important both in terms of fundamental structure-property relationships and for their performance in OPV devices. Deciphering these interactions will require a combination of polymer synthesis, structural characterization, and electronic testing. Implementation of these skills will result in: 1) the synthesis of new hole-conducting and electron-conducting non-conjugated polymers, 2) a description of charge transport in radical polymers such that improvement in the conductivity values of these functional macromolecules can occur, and 3) the utilization of these materials in OPV devices such that an environmentally-stable, low-cost alternative to existing charge collecting layers can be found. As such, completion of the research objectives will provide the fundamental scientific understanding to lay the foundation for a new area of polymer development and interfacial modifications in organic electronics with a deep impact in the organic photovoltaics and sustainable energy fields. This could lead to high-performance OPV devices that will help address current uncertainty in the global energy landscape. Furthermore, the basic discoveries regarding charge transport relationships in a new class of solid state polymeric conductors will have the potential to spread to other realms of organic electronics currently dominated by the conjugated materials.In addition to providing a concrete physical understanding of radical polymer conductors, this project will aid in the teaching and career development of graduate, undergraduate, and high school students through laboratory and outreach activities. For example, it will increase the participation of traditionally underrepresented groups in science and engineering through support of the Boudouris-founded Purdue Project SEED high school research experience. Bridging the disciplines of chemistry, polymer science, chemical engineering, and electrical engineering will afford the graduate, undergraduate, and high school students associated with this project a unique opportunity to engage in interdisciplinary, energy-related research that will have them well-prepared for future endeavors in academic and industrial circles. This synergistic relationship between research and educational activities will be of prime import in producing high impact scientific results, generating transformative technologies, and inspiring the next generation of sustainable energy scientists and engineers.