Pyromellitic Diimide (PyDI)-Based Molecular and Polymeric Electron-Transporting Semiconductors

“这项奖励是根据2009年美国复苏和再投资法案（公法111-5）资助的。”技术概述：苯四羧基二酰亚胺（PyDIs）是最著名的高绝缘聚酰亚胺电介质片段。该提案是建立在一个变革的概念，一个简单的PyDI结构是一个足够的共轭核心，用于构建基于聚合物的电子和能量换能器的载电子有机半导体。这种结构比已经研究过的更高的乙烯更容易获得，它是高度透明和化学稳定的，并导致可加工和电子可调谐的衍生物。虽然已经开发了许多小分子和聚合物空穴携带（p通道）半导体，但携带电子（n通道）的替代品清单虽然在增长，但仍然较少。可加工的n沟道半导体的例子特别少。大多数n-半导体的共轭核具有很高的熔点。那些少数可溶液处理的需要广泛的合成。这个提议发展了一个反直觉的想法，即PyDIs可以作为晶体管和其他器件中的分子和聚合物半导体。PI已经表明，PyDI半导体的电子迁移率可以达到0.1 cm2/Vs。由PyDI衍生物制成的晶体管可在空气中工作，并且具有非常高的通/关比。本研究旨在对PyDIs上的N和3,6- c取代进行系统研究，开发溶液可加工性，并将这些结构扩展到可打印聚合物中。要解决的基本问题包括通过取代的电子能级可调性，PyDI和萘四羧基二亚胺的相对优点，可加工固体中固体填料的保存，共轭和非共轭取代基和聚合物键的比较，分子固体与聚合物的可靠性，以及用于印刷的聚合物溶液的增强粘度。将确定各种衍生物的形态和晶体结构，以及相对于PyDIs可能混合或与其共享界面的其他材料的轨道能级。非技术总结：新的有机和聚合物材料，虽然基于通常与绝缘体相关的结构，但在这种情况下，将进一步为有机基电路，太阳能电池，电容器和热电技术提供机会。它们将用于本科和高中实验课教学的模块中。目前正在开发一门专门利用有机电子设备的课程，并将转移到主要的本科院校，如德鲁大学、马里兰大学巴尔的摩县分校和安妮阿伦德尔高中。这些模块还将呈现给高中教师研讨会，其中包括来自城市学区的不同参与者。对研究生和本科生的指导，包括来自霍华德大学的联合和访问少数民族学生，将被强调。

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."TECHNICAL SUMMARY: Pyromellitic (benzenetetracarboxylic) diimides (PyDIs) are best known as segments of highly insulating polyimide dielectrics This proposal is to build on the transformative concept that a simple PyDI structure is a sufficiently conjugated core for the construction of electron-carrying organic semiconductors for polymer-based electronics and energy transducers. This structure is more readily available than the higher rylenes already investigated, is highly transparent and chemically stable, and leads to processable and electronically tunable derivatives. While numerous small-molecule and polymeric hole-carrying (p-channel) semiconductors have been developed, the list of electron-carrying (n-channel) alternatives, while growing, remains smaller. There are particularly few examples of processable n-channel semiconductors. Most conjugated cores for n-semiconductors have very high melting points. Those few that are solution processable require extensive syntheses. This proposal develops the counterintuitive idea that PyDIs can function as molecular and polymeric semiconductors in transistors and other devices. The PI has already shown that PyDI semiconductors can have electron mobilities 0.1 cm2/Vs. Transistors made from PyDI derivatives are operable in air and have very high on/off ratios. This proposal is to perform a systematic study of N and 3,6-C substitution on PyDIs, develop solution processability, and extend these structures into printable polymers. Fundamental issues to be addressed include the electron energy level tunability through substitution, relative merit of PyDI and naphthalenetetracarboxylic diimides, preservation of solid state packing in processable solids, comparison of conjugated and nonconjugated substituents and polymer linkages, reliability of molecular solids versus polymers, and enhanced viscosities of polymer solutions for printing. The morphology and crystal structures will be determined for a wide range of derivatives, as will the orbital energy levels relative to other materials in which the PyDIs might be blended or with which they might share interfaces.NONTECHNICAL SUMMARY: New organic and polymeric materials, though based on a structure generally associated with insulators, will in this case further opportunities for organic based circuit, solar cell, capacitor, and thermoelectric technologies. They will be utilized in modules for undergraduate and high school laboratory course teaching. One particular course is being developed specifically to utilize organic electronic devices, and will be transferred to predominantly undergraduate institutions such as Drew University and University of Maryland-Baltimore County, and Anne Arundel High School. The modules will also be presented to high school teacher workshops that include a diverse mix of attendees from urban school districts. Mentoring of graduate and undergraduate students, including joint and visiting minority students from Howard University, will be emphasized.