Ionic liquid dynamics in nanoporous carbon: A pore-size- and temperature-dependent neutron spectroscopy study on supercapacitor materials
Mark Busch, Tommy Hofmann, B. Frick, Jan Peter Embs, Boris Dyatkin, Patrick Huber
Abstract
Ionic liquids imbibed in nanoporous carbons are promising hybrid materials for electrochemical energy storage, conversion and harvesting. These functionalities crucially depend on the ionic mobility in the pore space. The authors demonstrate that quasielastic neutron scattering, specifically the so-called fixed energy window experimental technique, is particularly suitable for a fast access of the confined ionic liquid's dynamic landscape as a function of pore-size and temperature. Compared to the bulk they find reduced self-diffusion mobilities. However, despite this slowing-down, the temperature range of the liquid state upon nanoconfinement is remarkably extended to much lower temperatures, which is beneficial for potential technical applications of such liquid-infused solids.