Molecular understanding of charge storage and charging dynamics in supercapacitors with MOF electrodes and ionic liquid electrolytes
File(s)
Accepted version
Supporting information
Author(s)
Type
Journal Article
Abstract
We performed constant-potential molecular dynamics simulations to analyse the double-layer structure and capacitive performance of supercapacitors composed of conductive metal-organic framework (MOF) electrodes and ionic liquids. The molecular modelling clarifies how ions transport and reside inside polarized porous MOFs, and then predicts the corresponding potential-dependent capacitance in characteristic shapes. The transmission line model was adopted to characterize the charging dynamics, which further allowed evaluation of the capacitive performance of this class of supercapacitors at the macroscale from the simulation-obtained data at the nanoscale. These 'computational microscopy' results were supported by macroscopic electrochemical measurements. Such a combined nanoscale-to-macroscale investigation demonstrates the potential of MOF supercapacitors for achieving unprecedentedly high volumetric energy and power densities. It gives molecular insights into preferred structures of MOFs for accomplishing consistent performance with optimal energy-power balance, providing a blueprint for future characterization and design of these new supercapacitor systems.
Date Issued
2020-05-01
Date Acceptance
2019-12-19
Citation
Nature Materials, 2020, 19, pp.552-558
ISSN
1476-1122
Publisher
Nature Research
Start Page
552
End Page
558
Journal / Book Title
Nature Materials
Volume
19
Copyright Statement
© The Author(s), under exclusive licence to Springer Nature Limited 2020
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/32015536
PII: 10.1038/s41563-019-0598-7
Grant Number
EP/H004319/1
Subjects
Science & Technology
Physical Sciences
Technology
Chemistry, Physical
Materials Science, Multidisciplinary
Physics, Applied
Physics, Condensed Matter
Chemistry
Materials Science
Physics
METAL-ORGANIC FRAMEWORKS
ENERGY-STORAGE
CAPACITANCE
TEMPERATURE
Nanoscience & Nanotechnology
Publication Status
Published
Coverage Spatial
England
Date Publish Online
2020-02-03