Coupled Ionic-Electronic-Structural Dynamics in Organic Mixed Conductors

在化学系大分子、超分子和纳米化学项目的支持下，康纳G.犹他州大学的Bischak正在阐明作为有机混合离子电子导体（OMIECs）的共轭聚合物中电子输运、离子运动和结构动力学之间的关系。 OMIECs是软聚合物半导体，可以传导电子和离子电荷。 这种独特的能力使它们特别适合与下一代生物电子，光电和储能设备相关的各种应用。 然而，对于这些应用中的许多应用，目前难以选择聚合物分子结构、聚合物加工条件和电解质的组合来实现特定的性能度量。 该项目将通过利用新型扫描探针成像方法的高空间分辨率和化学特异性以及传统和新型原位技术的互补套件来填补这些知识空白。 作为这项工作的结果建立的基本相关性有可能帮助指导合成化学家合成下一代的OMIEC共轭聚合物。 这项研究的跨学科性质将为高中，本科和研究生提供强大的培训和专业发展机会。 该项目还将支持一项外展工作，为当地高中化学教室提供价格实惠的3D打印光谱仪，以了解光物质相互作用，类似于用于询问OMIEC聚合物的光谱仪。该研究将重点研究有机混合离子-电子导体（OMIEC）以揭示离子运动、电子传输和结构动力学之间的关系。具有由烃、低聚（乙二醇）或羰基官能团组成的各种主链的聚（噻吩）将成为焦点，部分原因是它们是目前性能最高的OMIEC材料。 在第一个具体的目标，可逆和不可逆的结构动力学将使用半结晶和无定形聚合物的共混物进行研究，以调整结晶度和测量离子注入动力学作为结晶与无定形聚合物比率的函数。 第二个目标是将研究扩展到离子依赖效应。 最后，异质聚合物结构的影响将通过相关的纳米成像来解决，这些纳米成像将用于回答有关掺杂过程和结构动力学的基本问题。 这些综合努力有可能为化学设计元素提供新的见解，从而实现更有效的导电性。该研究旨在解决该领域的关键知识差距，目标是在此类系统中实现最佳离子和电子电导率的设计。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Macromolecular, Supramolecular and Nanochemistry program in the Division of Chemistry, Connor G. Bischak of the University of Utah is elucidating the relationship between electronic transport, ion motion, and structural dynamics in conjugated polymers that operate as organic mixed ionic-electronic conductors (OMIECs). OMIECs are soft polymeric semiconductors which can conduct both electronic and ionic charges. This unique ability makes them particularly suitable for a variety of applications of relevance to next-generation bioelectronic, optoelectronic and energy storage devices. However, for many of these applications, it is currently difficult to choose a combination of polymer molecular structure, polymer processing conditions, and electrolyte to achieve a specific performance metric. This project will fill these knowledge gaps by exploiting the high spatial resolution and chemical specificity of novel scanning probe imaging approaches, as well as a complementary suite of traditional and novel in situ techniques. Fundamental correlations established as a result of this work have the potential to help guide synthetic chemists towards synthesizing the next generation of OMIEC conjugated polymers. The interdisciplinary nature of this research will provide strong training and professional development opportunities for high school, undergraduate and graduate students. The project will additionally support an outreach effort to supply local high school chemistry classrooms with affordable 3D-printed spectrometers to learn about light-matter interactions, similar to those that are used to interrogate OMIEC polymers.This research will focus on investigating organic mixed ionic-electronic conductors (OMIECs) to uncover relationships between ion motion, electronic transport, and structural dynamics. Poly(thiophene)s with various backbones comprised of hydrocarbons, oligo (ethylene glycol)s, or carbonyl functionalities will be the focal points, in part because they are currently the highest performing OMIEC materials. In the first specific aim, reversible and irreversible structural dynamics will be investigated using blends of semicrystalline and amorphous polymers to tune the crystallinity and measure ion injection kinetics as a function of crystalline to amorphous polymer ratios. The second aim will extend studies to ion dependent effects. Finally, the impacts of heterogeneous polymer structure will be addressed through correlative nanoscale imaging that will be used to answer basic questions about the doping process and structural dynamics. The combined efforts have the potential to afford new insights into chemical design elements that enable more effective conductivity. This research aims to address critical knowledge gaps in the field with the goal of enabling design of optimal ionic and electronic conductivity in such systems.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.