Thin Layer Sonoelectrochemistry

在化学系化学测量和成像计划的支持下，爱荷华大学的Johna Leddy教授和她的团队将探索在超声波辐射的电极上改进催化作用。经典的说法是，化学反应的速度随着温度和压力的增加而增加。在超声波辐照溶液时，可以实现温度和压力的较大局部漂移。在薄层电化学池中，这些能量漂移被捕获在电极表面，并极大地增加了原本缓慢的电化学事件的速率。薄层声电化学是有效的，并用几个具有基础和技术重要性的反应的初步数据进行了证明。由于驱动超声换能器的能量税很低，在薄溶剂层中的超声作用可能提供一种提高表面反应速率的一般方法。该项目的总体目标是确定薄层声电化学提高界面速率的基本机制；绘制声频率和强度的依赖关系图；优化系统设计以最大限度地捕获声能；探索薄层声电化学最有效地加速电催化的机制和材料。在多相催化的基本原理以及电池和燃料电池等电化学能源技术中，薄层声电催化是一个潜在的变革性概念。该提议的智力优势包括一种新的、具有潜在变革性的方法，以促进包括电催化在内的多相反应，以及一种将实验和模型结合起来以确定通过超声提高界面速率的基本过程的研究方法。更广泛的影响包括改进的电化学能源技术、测量工具和训练有素的STEM研究人员。

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Professor Johna Leddy at University of Iowa and her group will explore improved catalysis at electrodes irradiated with ultrasound. Classically, rates of chemical reactions increase with temperature and pressure. On irradiation of solutions with ultrasound, large localized excursions of temperature and pressure can be achieved. In a thin layer electrochemical cell, these energetic excursions are captured at electrode surfaces and dramatically increase rates of otherwise slow electrochemical events. That thin layer sonoelectrochemistry is effective is demonstrated with preliminary data for several reactions of fundamental and technological importance. Because the energetic tax to drive ultrasonic transducers is low, sonication in a thin solvent layer may provide a general means to increase surface reaction rates.The global objectives of this project are to identify the fundamental mechanisms by which thin layer sonoelectrochemistry increases interfacial rates; to map dependencies on acoustic frequency and intensity; to optimize system design for maximum capture of acoustic energy; and to explore mechanisms and materials where thin layer sonoelectrochemistry most effectively accelerates electrocatalysis. Thin layer sonoelectrocatalysis is a potentially transformative concept in the fundamentals of heterogeneous catalysis and in electrochemical energy technologies such as batteries and fuel cells. The intellectual merits of the proposal include a new and potentially transformative means to facilitate heterogeneous reactions that include electrocatalysis and a research approach that couples experiments and models to identify the fundamental processes that drive enhanced interfacial rates ultrasonically. The broader impacts include improved electrochemical energy technologies, tools to make measurements, and well trained STEM researchers.