Robert Messinger

University of Arizona

Hosted by: Frederic Perras

Physical Seminar

Abstract

Molecular-Level Elucidation of Ionic & Electronic Charge Storage Mechanisms
in Rechargeable Aluminum Batteries

Rechargeable aluminum metal batteries are ideal for use on a global scale: aluminum is energy dense, low cost, inherently safe, earth abundant, and highly recyclable. Despite these advantages, their technological development has been hindered by fundamental challenges associated with aluminum electrochemistry. Few electrolytes enable the reversible electrodeposition of Al metal at room temperature, while few electrode materials exhibit high energy density and cycle life within those electrolytes. Here, I will discuss recent progress in our group in the molecular-scale design and understanding of positive electrode materials for rechargeable aluminum batteries. By coupling electrochemical experiments with solid-state nuclear magnetic resonance (NMR) spectroscopy, we elucidate new understanding of their ionic and electronic charge storage mechanisms.

For example, in Chevrel phase electrodes, we show that reversible aluminum-ion intercalation occurs simultaneously with electrochemical anionic redox, an unusual electron charge storage mechanism that differs fundamentally from those observed in lithium-ion intercalation electrodes.  In Al-organic batteries, we reveal that anthraquinone-based organic electrodes store charge by electrochemical enolization reactions coupled with charge-compensating complexation of polyatomic chloroaluminous cations. Overall, the results suggest design molecular-level design principles aimed at developing rechargeable aluminum batteries for diverse energy storage applications.

Bio

Robert J. Messinger is an Associate Professor and the Director of Graduate Studies in the Department of Chemical Engineering at The City College of New York (CCNY). He earned a B.S. in chemical engineering from The Ohio State University (2006) and a Ph.D. in chemical engineering from the University of California, Santa Barbara (2012). Afterwards, he studied physical chemistry and electrochemistry at the CNRS, France, first as a European Union Marie Curie Postdoctoral Fellow in Orléans (2012-2014) and then jointly with the CNRS and Grenoble Institute of Technology (2014-2015). At CCNY, his research group studies electrochemical materials, (electro)chemical processes, and multi-phase fluids for energy storage and recycling applications. He is an expert in nuclear magnetic resonance (NMR) spectroscopy. Prof. Messinger won an NSF CAREER award (2019) and is the Founding Director of the NASA-CCNY Center for Advanced Batteries for Space.