Inherent electrochemical activity of TiO2 (anatase, rutile) enhances the charge capacity of cathodes of lithium-sulfur batteries

0554275 - ÚFCH JH 2023 RIV DE eng J - Journal Article
Zlámalová, Magda - Pitňa Lásková, Barbora - Vinarčíková, Monika - Zukalová, Markéta - Kavan, Ladislav
Inherent electrochemical activity of TiO2 (anatase, rutile) enhances the charge capacity of cathodes of lithium-sulfur batteries.
Journal of Solid State Electrochemistry. Roč. 26, č. 3 (2022), s. 639-647. ISSN 1432-8488. E-ISSN 1433-0768
R&D Projects: GA ČR(CZ) GA20-03564S
Institutional support: RVO:61388955
Keywords : reduced graphene oxide * performance * carbon * host * separator * layers * Titanium dioxide * Lithium-sulfur battery * Coin cells * Mott-Schottky analysis * Flatband potential
OECD category: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)
Impact factor: 2.5, year: 2022
Method of publishing: Limited access

The addition of nanocrystalline titanium dioxide (P90) to a cathode of Li/S cell enhances its voltammetric charge capacity by 19%, from which only a small fraction (ca. 1%) is assignable to the intrinsic Li-storage in TiO2. The flatband potential of anatase (the main component of P90) and rutile (the second main component of P90) equals 2.1 V vs. Li+/Li for both anatase and rutile. The S-8 reduction is triggered at the same potential, confirming that TiO2 behaves like an ideally rectifying semiconductor electrode for sulfur. The modification of glass-fiber separator by P90 further improves the charge capacity of the Li/S cell. Titanium dioxide is active in the Li/S cell not only for immobilization of polysulfides on the sulphiphilic surface but also due to its inherent electrochemical activity for sulfur reduction at potentials negative to V-fb.
Permanent Link: http://hdl.handle.net/11104/0328906