Unveiling the electronic properties of native solid electrolyte interphase layers on Mg metal electrodes using local electrochemistry

Carla Santana Santos; Martina Romio; Yuri Surace; Nicolas Eshraghi; Marco Amores; Andreas Mautner; Christiane Groher; Marcus Jahn; Edgar Ventosa; Wolfgang Schuhmann

doi:10.1039/d3sc02840b

Titel

Unveiling the electronic properties of native solid electrolyte interphase layers on Mg metal electrodes using local electrochemistry

Autor*in

Carla Santana Santos

Analytical Chemistry – Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum

Martina Romio

Battery Technologies, Centre for Low-Emission Transport, AIT Austrian Institute of Technology GmbH

Yuri Surace

Battery Technologies, Centre for Low-Emission Transport, AIT Austrian Institute of Technology GmbH

... show all

Abstract

Magnesium-ion batteries (MIBs) are of considerable interest as environmentally more sustainable, cheaper, and safer alternatives to Li-ion systems. However, spontaneous electrolyte decomposition occurs due to the low standard reduction potential of Mg, leading to the deposition of layers known as native solid electrolyte interphases (n-SEIs). These layers may inhibit the charge transfer (electrons and ions) and, therefore, reduce the specific power and cycle life of MIBs. We propose scanning electrochemical microscopy (SECM) as a microelectrochemical tool to locally quantify the electronic properties of n-SEIs for MIBs. These interphases are spontaneously formed upon contact of Mg metal disks with organoaluminate, organoborate, or bis(trifluoromethanesulfonyl)imide (TFSI)-based electrolyte solutions. Our results unveil increased local electronic and global ionic insulating properties of the n-SEI formed when using TFSI-based electrolytes, whereas a low electronically protecting character is observed with the organoaluminate solution, and the organoborate solution being in between them. Moreover, ex situ morphological and chemical characterization was performed on the Mg samples to support the results obtained by the SECM measurements. Differences in the electronic and ionic conductivities of n-SEIs perfectly correlate with their chemical compositions.

Objekt-Typ

journal article

Sprache

Englisch [eng]

Persistent identifier

phaidra.univie.ac.at/o:2066516

DOI

10.1039/d3sc02840b

Erschienen in

Titel

Chemical Science

Band