posted on 2017-10-13, 00:00authored byAndrea Paolella, Dharminder Laul, Vladimir Timoshevskii, Wen Zhu, Sergio Marras, Giovanni Bertoni, Alexander Sean Wahba, Gabriel Girard, Catherine Gagnon, Lisa Rodrigue, Basile Commarieu, Abdelbast Guerfi, Raynald Gauvin, Michel L. Trudeau, Ashok Vijh, Michel Armand, Karim Zaghib
Recently
many observations related to the catalytic effects of
layered metal disulfide versus polysulfide electrochemistry were documented.
In this work, we investigated the reactivity of layered WS2 in a Li–S battery and observed a chemical reaction involving
the removal of W ions by polysulfides. The presence of metallic tungsten
nanoparticles in the sulfur cathode is the result of W ion oxidation
reaction and subsequent recrystallization during cycling. In situ
Raman spectroscopy and ex situ transmission electron microscopy were
used in order to clarify the reaction mechanism.