Abstract
This study analyzed the dynamics of ionic liquid electrolyte inside of defunctionalized, hydrogenated, and aminated pores of carbide-derived carbon supercapacitor electrodes. The approach tailors surface functionalities and tunes nanoporous structures to decouple the influence of pore wall composition on capacitance, ionic resistance, and long-term cyclability. Quasi-elastic neutron scattering probes the self-diffusion properties and electrode-ion interactions of electrolyte molecules confined in functionalized pores. Room-temperature ionic liquid interactions in confined pores are strongest when the hydrogen-containing groups are present on the surface. This property translates into higher capacitance and greater ion transport through pores during electrochemical cycling. Unlike hydrogenated pores, aminated pores do not favorably interact with ionic liquid ions and, subsequently, are outperformed by defunctionalized surfaces.
| Original language | English |
|---|---|
| Pages (from-to) | 631-641 |
| Number of pages | 11 |
| Journal | Progress in Natural Science: Materials International |
| Volume | 25 |
| Issue number | 6 |
| DOIs | |
| State | Published - Dec 1 2015 |
| Externally published | Yes |
Funding
This study was supported by the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy , Office of Science, Office of Basic Energy Sciences. Quasi-elastic neutron scattering experiments (at ORNL) were made available through the Scientific User Facilities Division, Office of Basic Energy Sciences, US Department of Energy. The authors thank Francis W. Richey and Maria R. Lukatskaya (Drexel University) for assistance with dynamic water vapor sorption and SEM analysis.
| Funders | Funder number |
|---|---|
| U.S. Department of Energy | |
| Office of Science | |
| Basic Energy Sciences |
Keywords
- Carbide-derived carbon
- Energy storage
- Neutron scattering
- Porous materials
- Supercapacitor
- Surface chemistry