Abstract
Developing better energy storage devices depends on comprehending the underlying mechanisms involved in charge storage. With the continuous conception of new electrolytes, this task becomes progressively more urgent and complex. An example is the utilization of co-solvated concentrated solutions. While these show promising electrochemical responses, their dynamic properties (especially under confinement) and their relationships with performance are not fully understood. Here, we combined modified step potential electrochemical spectroscopy and quasielastic neutron scattering to investigate systems composed of activated mesoporous carbon (AMC) and concentrated solutions of lithium bis(trifluoromethanesulfonyl)imide in acetonitrile co-solvated with either toluene or acetone. We report that acetone does not impair surface-controlled mechanisms, contrary to the case with toluene, which competes with charged species to populate the AMC’s pores without contributing to charge storage. In turn, toluene promotes a greater overall capacitance owing to Faradaic processes, which may be related to changes in the solvation structures under confinement.
| Original language | English |
|---|---|
| Pages (from-to) | 8903-8909 |
| Number of pages | 7 |
| Journal | Journal of Physical Chemistry Letters |
| Volume | 15 |
| Issue number | 34 |
| DOIs | |
| State | Published - Aug 29 2024 |
Funding
This research used resources at the Spallation Neutron Source (IPTS 27122) and the Center for Nanophase Materials Sciences, a U.S. Department of Energy (DOE) Office of Science User Facility operated by the Oak Ridge National Laboratory (ORNL). This work was supported as part of the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center funded by the DOE Office of Science, Office of Basic Energy Sciences. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the Office of Science of the DOE under Contract DE-AC0205CH11231. ORNL is managed by UT-Battelle, LLC, for the DOE under Contract DEAC05-00OR22725. This manuscript has been authored by UT-Battelle, LLC, under Contract DE-AC05-00OR22725 with the U.S. Department of Energy (DOE). The U.S. government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript or allow others to do so for U.S. government purposes. The DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( https://www.energy.gov/doe-public-access-plan ). Acknowledgments