Thin Layer Sonoelectrochemistry

University Of Iowa, Iowa City IA

Investigators

Abstract

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.