Supercapacitor Capacitance Exhibits Oscillatory Behavior as a Function of Nanopore Size
- ORNL
Supercapacitors composed of slit-shaped micropores ranging in size from 0.67 to 1.8 nm in a room-temperature ionic liquid were studied to investigate the dependence of capacitance (C) on the pore size (d) using molecular dynamics simulations. The capacitance versus pore size (i.e., the Cd curve) was found to exhibit two peaks located at 0.7 and 1.4 nm, respectively. Specifically, as the pore shrinks from 1.0 to 0.7 nm, the capacitance of the micropore increases anomalously, in good agreement with experimental observations. We report herein that the second peak within 1.0 to 1.8 nm is a new feature of the Cd curve. Furthermore, by analogy to the wave interference, we demonstrate that the interference of two electrical double layers near each slit wall does not only explain the entire Cd curve, including the anomalous character, but also predicts the oscillatory behavior of Cd curve beyond 1.8 nm.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- DE-AC05-00OR22725
- OSTI ID:
- 1033173
- Journal Information:
- Journal of Physical Chemistry Letters, Vol. 2, Issue 22; ISSN 1948-7185
- Country of Publication:
- United States
- Language:
- English
Similar Records
Oscillation of Capacitance inside Nanopores
Complex Capacitance Scaling in Ionic Liquids-Filled Nanopores