Tuning Pore Size to Enhance the Capacitance of Supercapacitors

Scientific Achievement

Simulations of nanoporous super-capacitors confirm and help to understand the anomalous increase in capacitance observed in experiment when the pore size is close to the ion size (0.7 nm).

Significance and Impact

The results point to a novel method for tuning supercapacitors by manipulating pore size and/or electrolyte ion size.

Research Details

Tuning Pores

Left: MD simulation of capacitance versus pore size (in nm) compared to experiment. Right: Oscillation in capacitance versus pore size (in ion diameters of 0.7 nm) simulated by DFT.

References: [1] De-en Jiang, Zhehui Jin, and Jianzhong Wu, Oscillation of Capacitance inside Nanopores, Nano Lett., 11, 5373-5377 (2011) [DOI: 10.1021/nl202952dExternal link].

[2] Guang Feng and Peter T. Cummings, Supercapacitor Capacitance Exhibits Oscillatory Behavior as a Function of Nanopore Size, J. Phys. Chem. Lett., 2, 2859-2864 (2011) [DOI: 10.1021/jz201312eExternal link].

[*] Original experiment (not EFRC-funded): Celine Largeot, Cristelle Portet, John Chmiola, Pierre-Louis Taberna, Yury Gogotsi, and Patrice Simon, Relation between the Ion Size and Pore Size for an Electric Double-Layer Capacitor, J. Am. Chem. Soc., 130, 2730 (2008) [DOI: 10.1021/jz201312eExternal link].

Support: Work was performed at Oak Ridge National Laboratory and supported by the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an EFRC led by David Wesolowski at Oak Ridge National Laboratory.

Last modified: 3/27/2013 12:28:19 PM