Probing the Mesoscale Structure of Complex Electrode-Electrolyte Interfaces
EMSL Project ID
48374
Abstract
Molecular interactions at electrode-electrolyte interface are pivotal to the modern energy storage/conversion and microelectronic devices. However, our predictive level understanding about the impact of electrode surface chemistry and nature of electrolyte ions on their molecular level interactions is seriously limited. This impedes our ability to design and control optimal interfaces. This work will address the intricacy of ionic liquid (IL) based electrolytes (i.e., densely packed asymmetric ions) and complex electrode surface chemistry (e.g., surface functional groups) that dictate short- and long-range molecular interactions, and govern macroscopic properties such as electrical double layer (EDL). These structural and dynamic changes of IL based electrolyte molecules would span over wide spatial (up to 10 nm) and temporal regions (up to few sec), which require analysis using multiple techniques. Therefore, a major challenge is to access the entire molecular process under modern interfaces using suitable in situ probes. In the proposed research, a combined in-situ XPS and NMR probing will be used to explore the short-range structure and long-range molecular ordering of electrolyte molecules near charged electrodes. With these molecular insights as guidance, a realistic statistical and electronic structure based computational analysis will be performed. From this optimized calculation, EDL's critical functionalities (e.g., capacitance) will be calculated and compared with macroscopic experimental results. Consilience through these combined multi-modal experimental and theoretical approaches will provide the critical structure-property relationship of modern interfaces.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2014-10-01
End Date
2016-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Kerisit S, M Vijayakumar, KS Han, and KT Mueller. 2015. "Solvation structure and transport properties of alkali cations in dimethyl sulfoxide under exogenous static electric fields." The Journal of Chemical Physics 142:224502. doi:10.1063/1.4921982