Synthesis of ternary transition metal fluorides Li ₃MF ₆via a sol-gel route as candidates for cathode materials in lithium-ion batteries

authored by

Julia Kohl, Dennis Wiedemann, Suliman Nakhal, Patrick Bottke, Noel Ferro, Thomas Bredow, Erhard Kemnitz, Martin Wilkening, Paul Heitjans, Martin Lerch

Abstract

A sol-gel route for ternary lithium fluorides of transition metals (M) is presented allowing the synthesis of Li ₃MF ₆-type and Li ₂MF ₅-type compounds. It is based on a fluorolytic process using transition metal acetylacetonates as precursors. The domain size of the obtained powders can be controlled by modifying the conditions of synthesis. ⁶Li and ⁷Li magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy is used to study local environments of the Li ions in orthorhombic and monoclinic Li ₃VF ₆ as well as Li ₂MnF ₅. The number of magnetically inequivalent Li sites found by MAS NMR is in agreement with the respective crystal structure of the compounds studied. Quantum chemical calculations show that all materials have high de-lithiation energies making them suitable candidates to be used as high-voltage battery cathode materials.

Organisation(s)

Institute of Physical Chemistry and Electrochemistry

External Organisation(s)

Technische Universität Berlin
Graz University of Technology
University of Bonn
Humboldt-Universität zu Berlin (HU Berlin)

Type

Article

Journal

Journal of Materials Chemistry

Volume

22

Pages

15819-15827

No. of pages

9

ISSN

0959-9428

Publication date

21.08.2012

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

General Chemistry, Materials Chemistry

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1039/c2jm32133e (Access: Unknown)
https://doi.org/10.1039/c2jm90181a (Access: Unknown)