NER: Engineering Stable Nanoscale Conducting / Insulating Polymer Interfaces: Combinatorial Exploratory Research

由于具有吸引力的范德华(VDW)相互作用，薄膜在厚度低于100 nm时可能变得不稳定。这个问题在导电和半导体聚合物中尤其严重，因为它们具有较大的Hamaker常数。VDW的不稳定性会导致去湿，在纳米级薄膜加工中必须避免。然而，防止这些系统中的VDW不稳定的可靠方法尚未出现。未能开发出控制不稳定性的策略，严重限制了纳米尺度导电聚合物薄膜的使用。为了解决这一关键限制，本研究将探索一种稳定纳米级导电/绝缘薄膜双层的创新方法。研究计划和意义。纳米级导电聚合物器件需要导电/绝缘界面的多层连接。由于Hamaker常数失配，VDW不稳定性很可能出现在这些结点上。这项研究将开发一种探索性的方法来防止聚合物双层导体/绝缘体界面的VDW不稳定性。由于缺乏先前关于纳米级导电聚合物润湿稳定性的研究和理论，导致该项目具有探索性、高风险的性质。风险增加了，因为在测试假设所需的许多样本上保持一致的底物化学的实验困难。为了克服这一实验效率的限制，将使用高通量测量方法来研究双层稳定性的可行性。具体目标：1)将确定防止VDW不稳定性所需的参数，以模型双层薄膜系统：聚(3-十一环联噻吩基)(PUBT)/聚苯乙烯(PS)，以及2)稳定性测量将与Hamaker常数模型进行比较，以确定其在预测纳米双层稳定性方面的有效性。这项拟议的工作将首次系统地测量绝缘体/半导体和绝缘体/导体薄膜双层的VDW稳定性。这一探索将设置重要的限制，并证明在设备架构中结合纳米级导体/绝缘体连接的可行性。教育计划和意义。PI的教育目标是增加佐治亚理工学院表面和胶体科学教学过程的内容、广度和包容性。为了满足这些需求，这项研究将补充PI的持续教育努力：*开发表面和胶体科学化学工程研究生课程*为本科工程课程提供互联网表面讲座范例*积极招募当地社区、少数族裔和代表性不足的学生参与工程研究。

Thin films can become unstable at thicknesses below 100 nm, due to attractive van der Waals (VDW) interactions. This problem is particularly severe in conducting and semiconducting polymers, which have large Hamaker constants. VDW instability results in dewetting and must be avoided in nanoscale film processing. Yet, robust methods for preventing VDW instability in these systems have not emerged. A failure to develop strategies to control instability places severe limits on the use of conducting polymer thinfilms at nanoscale dimensions. To address this critical limitation, this research will explore an innovative method to stabilize nanoscale conducting / insulating film bilayers.Research Plan and Significance. Nanoscale conducting polymer devices require multilayered junctions of conducting / insulating interfaces. VDW instability is likely to occur at these junctions due to Hamaker constant mismatch. This research will develop an exploratory method to prevent VDW instability at polymer bilayer conductor / insulator interfaces.The lack of previous research and theory on nanoscale conductive polymer wetting stability leads to the exploratory, high-risk nature of this project. The risk is increased by the experimental difficulty in maintaining consistent substrate chemistry over the many samples needed to test hypotheses. To overcome this limitation in experimental efficiency, a high-throughput measurement method will be used for feasibility studies of bilayer stability.Specific Aims: 1) The parameters required to prevent VDW instability will be determined for a model bilayer thin film system: poly(3-undecybithiophene) (PUBT) / polystyrene (PS), and 2) Stability measurements will be compared to a Hamaker constant model to ascertain its effectiveness in predicting stability of nanoscale bilayers.Outcomes. The proposal work will provide the first systematic measurements of VDW stability of insulator/semiconductor and insulator/conductor thin film bilayers. This exploration will set important limitations and demonstrate the feasibility of incorporating nanoscale conductor / insulator junctions in device architectures.Educational Plan and Significance. The educational goal of the PI is to increase the content, breadth, and inclusiveness of the instructional process for surface and colloid science at Georgia Tech. To meet these needs this research will supplement the PI's continuing educational thrusts:* Development of a graduate course in surface and colloid science chemical engineering* Internet-available surface lecture examples for undergraduate engineering courses* Active recruitment of the local community, minority, and underrepresented students in engineering research.