title: Confinement, Desolvation, And Electrosorption Effects on the Diffusion of Ions in Nanoporous Carbon Electrodes.
abstract: Supercapacitors are electrochemical devices which store energy by ion adsorption on the surface of a porous carbon. They are characterized by high power delivery. The use of nanoporous carbon to increase their energy density should not hinder their fast charging. However, the mechanisms for ion transport inside electrified nanopores remain largely unknown. Here we show that the diffusion is characterized by a hierarchy of time scales arising from ion confinement, solvation, and electrosorption effects. By combining electrochemistry experiments with molecular dynamics simulations, we determine the in-pore conductivities and diffusion coefficients and their variations with the applied potential. We show that the diffusion of the ions is slower by 1 order of magnitude compared to the bulk electrolyte. The desolvation of the ions occurs on much faster time scales than electrosorption.
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS , Laboratoire PHENIX, F-75005 Paris, France.|CIRIMAT, UMR CNRS 5085, Université Paul Sabatier , Bat. 2R1, 118 route de Narbonne, 31062 Toulouse Cedex 9, France.|Réseau sur le Stockage Electrochimique de l'Energie (RS2E), FR CNRS 3459 , 80039 Amiens Cedex, France.
authors.forename: Clarisse
authors.initials: C
authors.lastname: Pean
authors.affiliation: CIRIMAT, UMR CNRS 5085, Université Paul Sabatier , Bat. 2R1, 118 route de Narbonne, 31062 Toulouse Cedex 9, France.|Réseau sur le Stockage Electrochimique de l'Energie (RS2E), FR CNRS 3459 , 80039 Amiens Cedex, France.
authors.forename: Barbara
authors.initials: B
authors.lastname: Daffos
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS , Laboratoire PHENIX, F-75005 Paris, France.|Réseau sur le Stockage Electrochimique de l'Energie (RS2E), FR CNRS 3459 , 80039 Amiens Cedex, France.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Rotenberg
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS , Laboratoire PHENIX, F-75005 Paris, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Levitz
authors.affiliation: Maison de la Simulation, USR 3441, CEA, CNRS, INRIA, Université Paris-Sud, Université de Versailles , F-91191 Gif-sur-Yvette, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Haefele
authors.affiliation: CIRIMAT, UMR CNRS 5085, Université Paul Sabatier , Bat. 2R1, 118 route de Narbonne, 31062 Toulouse Cedex 9, France.|Réseau sur le Stockage Electrochimique de l'Energie (RS2E), FR CNRS 3459 , 80039 Amiens Cedex, France.
authors.forename: Pierre-Louis
authors.initials: PL
authors.lastname: Taberna
authors.affiliation: CIRIMAT, UMR CNRS 5085, Université Paul Sabatier , Bat. 2R1, 118 route de Narbonne, 31062 Toulouse Cedex 9, France.|Réseau sur le Stockage Electrochimique de l'Energie (RS2E), FR CNRS 3459 , 80039 Amiens Cedex, France.
authors.forename: Patrice
authors.initials: P
authors.lastname: Simon
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS , Laboratoire PHENIX, F-75005 Paris, France.|CIRIMAT, UMR CNRS 5085, Université Paul Sabatier , Bat. 2R1, 118 route de Narbonne, 31062 Toulouse Cedex 9, France.|Maison de la Simulation, USR 3441, CEA, CNRS, INRIA, Université Paris-Sud, Université de Versailles , F-91191 Gif-sur-Yvette, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Salanne