Issue 19, 2020

A first-principles investigation of the structural and electrochemical properties of biredox ionic species in acetonitrile

Abstract

Biredox ionic liquids are a new class of functionalized electrolytes that may play an important role in future capacitive energy storage devices. By allowing additional storage of electrons inside the liquids, they can improve device performance significantly. However current devices employ nanoporous carbons in which the diffusion of the liquid and the adsorption of the ions could be affected by the occurrence of electron-transfer reactions. It is therefore necessary to understand better the thermodynamics and the kinetics of such reactions in biredox ionic liquids. Here we perform ab initio molecular dynamics simulations of both the oxidized and reduced species of several redox-active ionic molecules (used in biredox ionic liquids) dissolved in acetonitrile solvent and compare them with the bare redox molecules. We show that in all the cases, it is necessary to introduce a two Gaussian state model to calculate the reaction free energies accurately. These reaction free energies are only slightly affected by the presence of the IL group on the molecule. We characterize the structure of the solvation shell around the redox active part of the molecules and show that in the case of TEMPO-based molecules strong reorientation effects occur during the oxidation reaction.

Graphical abstract: A first-principles investigation of the structural and electrochemical properties of biredox ionic species in acetonitrile

Supplementary files

Article information

Article type
Paper
Submitted
10 Des 2019
Accepted
07 Feb 2020
First published
13 Feb 2020

Phys. Chem. Chem. Phys., 2020,22, 10561-10568

A first-principles investigation of the structural and electrochemical properties of biredox ionic species in acetonitrile

K. G. Reeves, A. Serva, G. Jeanmairet and M. Salanne, Phys. Chem. Chem. Phys., 2020, 22, 10561 DOI: 10.1039/C9CP06658F

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements