CAREER: Design Rules for Electrical Transport in Suspensions of Conductive Particles

软材料由微观建筑块组成，其纳米级的相互作用可以被设计成产生完全不同的材料行为。悬浮液是一类含有分散在流体中的固体颗粒的软材料。新的电化学能量存储技术的发展已经引起了对理解包含导电纳米颗粒和微米颗粒的悬浮液的性质的新的兴趣，特别是对于需要表现出低粘度和高电导率的悬浮液的应用。虽然稠密悬浮液的流变学具有坚实的理论和实验基础，但对电特性的了解较少。这种知识差距为设计具有最佳性能的悬架提出了独特的挑战和机会。该项目将通过将新的合成技术与先进的结构和电学表征方法相结合来应对这一挑战，以弥合目前在理解导电颗粒悬浮液中电子传输方面的差距。该项目还将为未来的劳动力提供软材料特性及其在新兴和当代社会挑战中的潜在应用方面的基础知识。受最近对极性和非极性溶剂中炭黑悬浮液的流变电测量的启发，这个项目将测试粒子动力学在介导悬浮液中的电子传输中发挥重要而未被重视的作用的假设。导电粒子我们的目标是用三种新的方法来检验这一假设。新的合成方法将控制导电纳米颗粒和微米颗粒之间的大小，形状和相互作用，而新的流变电表征技术将允许直接量化电传输特性。这些新的合成和表征方法将通过使用小角散射技术的微结构测量来增强。这三种方法的结合将导致设计规则的发展，可用于工程的电化学能量存储技术和其他有用的目的悬架的电气性能。这一奖项反映了NSF的法定使命，并已被认为是值得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的支持。

Soft materials consist of microscopic buildings blocks whose nanoscale interactions can be engineered to yield radically different material behaviors. Suspensions are one class of soft material that contain solid particles dispersed in a fluid. The development of new electrochemical energy storage technologies has generated renewed interest in understanding the properties of suspensions containing electrically conductive nano- and micro- particles, especially for applications requiring suspensions that exhibit low viscosity and high electrical conductivity. While the rheology of dense suspensions has a firm theoretical and experimental basis, the electrical properties are less well understood. This knowledge gap presents a unique challenge and opportunity to design suspensions with optimal properties. This project will address this challenge by combining new synthesis techniques with advanced structural and electrical characterization methods to bridge the current gap in understanding electron transport in fluid suspensions of conducting particles. This project will also prepare the future workforce with foundational knowledge in the properties of soft materials and their potential application to emerging and contemporary societal challenges.Motivated by recent rheo-electric measurements of suspensions of carbon black in polar and non-polar solvents, this project will test the hypothesis that particle dynamics play a significant and underappreciated role in mediating electron transport in fluid suspensions of conducting particles. The objective will be to test this hypothesis with three novel approaches. New synthetic approaches will control the size, shape, and interactions between conductive nano- and micro-particles, while new rheo-electric characterization techniques will allow for direct quantification of electrical transport characteristics. These new synthetic and characterization approaches will be augmented by microstructural measurements using small angle scattering techniques. The combination of these three approaches will result in the development of design rules that can be used to engineer the electrical properties of suspensions for electrochemical energy storage technologies and other useful purposes.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.