Excellence in Research - Collaborative: Hierarchical multilayered block copolymer dielectrics with z-gradient nanofiller for capacitive energy storage and gate dielectric

该项目由历史上的黑人学院和大学本科项目-卓越研究项目(HBCU-UP EIR)资助。非技术概述：轻质聚合物薄膜在与便携式储能设备相关的柔性电子设备中的潜在应用引起了人们的极大兴趣，包括电池、电容器、集成太阳能电池和软驱动。在这方面，高能量密度电容储能的新方法最近显示出利用多层聚合物薄膜进行高电能储能的显著潜力。实质上，多层内的多个界面作用于顺序地阻止电介质聚合物膜的电击穿，这决定了柔性电容器的能量存储上限。认识到击穿遵循电极之间越来越多的分支不对称路径(很像闪电击中地面)，正极上的电势最高，这项工作将系统地设计和探索杂化聚合物多层(四层)是否可以通过与不对称击穿路径相反的聚合物层击穿特性的不对称性在结构上进行“反向工程”。该方法旨在利用自组装嵌段共聚物形成多层膜，并将其与分散的无机纳米膜的使用相结合，以提高储能能力。成功的结果可能会对柔性电子行业产生重大影响。这一多学科团队的努力涉及霍华德大学和杰克逊州立大学(历史上的黑人学院大学)和休斯顿大学，这是一个少数民族服务机构，有大量的机构内和机构间的教育、培训和研究活动。该项目将在每个校园安排为期一天的纳米复合材料年度轮换会议，以教育科学家、当地教师和当地大学在校学生纳米技术的巨大可能性。将培训一支训练有素的纳米技术专家队伍，以应对国家劳动力需求的挑战，并制作可向科学界和更广泛的社会传播的同行评议的科学和技术出版物。该计划旨在为纳米科学和纳米工程领域的潜在研究人员制定网络可访问的培训协议。技术概述；固态柔性电容器的根本高能量密度和超快充放电率(脉冲功率)是至关重要的。能量存储密度受可跨电极施加的最大电场的限制。目前用于脉冲功率应用的技术使用聚合物作为介质的选择，因为它们具有高电阻、低介质损耗、自愈能力、可成形性和灵活性。然而，这些材料并不能满足下一代薄膜介质对高电压、高能量密度电子器件的所有要求。计划中的工作是基于这样的假设，即分子组装的电容层的反对称z结构四层设计可以精确地对抗从正极到负极的电树状击穿级联的不对称。这种反对称膜结构考虑了在正极具有极高阻击穿能力的自组装多层嵌段共聚物的四层结构，根据电树状击穿的观点，正极处的电场强度最高。随后的层也是嵌段共聚结构，具有平面内排列的纳米片，以防止电场级联击穿。第三层设计为包含隔离在宏观有序嵌段共聚物层中的高介电纳米颗粒，这也为场效应晶体管和逻辑设计等2D半导体器件提供了一种栅电介质策略，与传统介质相比，逻辑设计具有更强的功能。最后，使用了无缺陷的底部聚合物层，这将防止滴流到负极。由霍华德大学和杰克逊州立大学(历史上的黑人学院大学)和休斯顿大学(一个少数民族服务机构)组成的多学科团队将致力于培养一支有才华的纳米技术专家队伍，以应对国家劳动力需求的挑战。关于纳米科学和纳米工程研究的网络模块将提供给年轻和感兴趣的研究人员和普通公众。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project is funded by the Historically Black Colleges and Universities Undergraduate Program - Excellence in Research program (HBCU-UP EiR). NON-TECHNICAL SUMMARY:There is much interest in use of lightweight polymer films for potential applications in flexible electronics related to portable energy storage devices, including batteries, capacitors, integrated solar cells and soft-actuation. In this regard, new approaches to high-energy density capacitive energy storage have recently demonstrated notable potential for high electrical energy storage using multilayered polymer films. Essentially the multiple interfaces within the multilayer act to sequentially block electrical breakdown of the dielectric polymer film that determines the upper limit of energy storage of the flexible capacitor. Recognizing that the breakdown follows an increasingly branched asymmetric pathway between electrodes (much like lightning bolts striking the earth), with the highest potential at the positive electrode, the work will systematically design and explore whether hybrid polymer multilayers (tetra-layered) can be structurally "reversed-engineered" with an asymmetry in polymer-layer breakdown properties that counters the asymmetric breakdown pathway. The approach aims to use self-assembling block copolymers for multilayer formation and combines it with the use of dispersed inorganic nanofillers to boost the energy storage capacity. Successful outcome can have a significant impact on the flexible electronics industry. This multidisciplinary team effort involves Howard University and Jackson State University (Historically Black College Universities) and University of Houston, a Minority Serving Institution, with significant amounts of intra and inter-institutional educational, training and research activities. The project will arrange a yearly rotational day-long conference on nanocomposites at each of the campuses to educate scientists, local teachers and local college bound students about the vast possibilities of nanotechnology. A trained cadre of talented nanotechnologists will be trained to address the challenges of the nation's workforce needs and produce peer reviewed scientific and technological publications that can be disseminated to the scientific community and broader society. The program aims to make web-accessible training protocols to prospective researchers in the field of nanoscience and nanoengineering.TECHNICAL SUMMARY;Fundamentally high energy densities and ultrafast charge-discharge rates (pulsed power) in solid state-flexible capacitors are of fundamental importance. The energy storage density is limited by the maximum electric field that can be applied across the electrodes. Current technologies for pulsed power applications utilize polymers as the dielectric of choice due to their high electrical resistance, low dielectric loss, self healing capability, formability and flexibility. However, these materials do not meet all of the requirements of the next-generation film dielectrics for high voltage and high energy density electronic devices. The planned work is based on the hypothesis that an anti-symmetric z-structured tetra-layered design of molecularly assembled capacitive elemental layers can precisely counter the asymmetry of the electrical treeing breakdown cascade from the positive to the negative electrode. The anti-symmetric film structure considers a tetra-layer with an extremely high breakdown prevention self-assembling multilayered block copolymer at the positive electrode where E-field strength is highest as per electrical treeing breakdown view-point. The subsequent layer is also a block copolymer structure with in-plane aligned nanosheets to forestall E-field cascade breakdown. The third layer is designed to contain high dielectric nanoparticles sequestered within a macroscopically ordered block copolymer layer, which also provides a strategy of gate dielectric for 2D semiconductor devices such as field-effect transistors and logic design with enhanced functionalities compared to the conventional dielectrics. Finally, a defect-free bottom polymer layer is used, which will prevent trickle-current to the negative electrode. A multidisciplinary team between Howard University and Jackson State University (Historically Black College Universities), and University of Houston, a Minority Serving Institution, will work towards training a cadre of talented nanotechnologists to face the challenges of the nation's workforce needs. Web modules on nanoscience and nanoengineering research for young and interested researchers and the general public will be made available.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.