Collaborative Research: U.S.-Ireland R&D Partnership: Full Atomistic Understanding of Solid-Liquid Interfaces via an Integrated Experiment-Theory Approach

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

The worldwide deployment of renewable energy requires efficient electrochemical systems, such as batteries, supercapacitors, and fuel cells. In most of these systems, the energy conversion and storage processes rely crucially on the interface between solid electrodes and liquid electrolytes. However, the fundamental atomic and molecular structure at these electrified interfaces remains elusive. The goal of the project is to achieve an atomistic understanding of the structure and reaction dynamics of electrode-electrolyte interfaces, and provide design principles for various low-cost, carbon-based electrochemical systems. Through international collaborations with the University College Dublin and Ulster University, the PIs will develop an integrated experimental imaging - atomistic simulation method. The technical outcomes of the project will facilitate the design and engineering of efficient electrochemical energy conversion and storage systems. The educational efforts of the project will build and incorporate demo devices of electrochemical cells and materials imaging platforms into a series of education and outreach activities both domestically and internationally. The project will train the graduate and undergraduate students with skills in both experimental and simulation methods and provide them with an international collaborative research experience. The project will contribute to efforts to educate the public on the basic mechanisms of renewable energy conversion and storage. The project’s aim is to achieve a thorough atomistic understanding of electrochemical processes by determining the 3D structure of electrode-electrolyte interfaces, including both the surface of the solid electrodes and the liquid solvation layers. The project’s approach will integrate molecular dynamics and density functional theory simulations with 3D atomic-resolution force microscopy experiments to achieve a joint experiment-theory platform for precise understanding and prediction of electrochemical interfaces. The platform will be used to unravel the solvation layer structure that is responsible for energy storage in carbon-based supercapacitors, and the solvent-included atomistic kinetics of electrocatalytic reactions on single-atom catalysts. The project will produce fundamental models of solid-liquid interfaces that consider the inherent atomic-scale heterogeneities. Furthermore, the thorough determination of the atomistic interfacial structure and catalytic activities of single-atom catalysts will shed light on the unconventional scaling relationships of catalysts with nonuniform structures. This will be an important step towards a more predictive, molecular-level theory beyond the widely accepted "Sabatier Principle" for heterogeneous catalysis and electrocatalysis. The results will significantly foster the design and engineering of electrochemical interfaces for low-cost, highly efficient renewable energy applications. 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.