Synthesis of Surface-Functionalized WS2 Nanosheets and Performance as Li-Ion Battery Anodes
Open Access
- 22 May 2012
- journal article
- research article
- Published by American Chemical Society (ACS) in The Journal of Physical Chemistry Letters
- Vol. 3 (11), 1523-1530
- https://doi.org/10.1021/jz300480w
Abstract
Separation of bulk tungsten disulfide (or WS2) into few-layer two-dimensional (2-D) crystals is of interest because of their high surface area for certain chemical processes and size-dependent optical and electronic characteristics. Herein, we demonstrate a process that involves the physical separation of weakly bonded WS2 layers by use of a strong acid treatment (chlorosulfonic acid) at 2 mg/mL, followed by quenching in deionized (DI) water. X-ray photoelectron spectroscopy of the superacid-treated WS2 suggests the formation of W–O type bonds, signifying oxidation of tungsten and reduction of the sulfur phase. Thermogravimetric analysis showed a three-phase weight-loss pattern, suggesting acid functionalization of WS2 surfaces. We also studied the electrochemical behavior of an acid-treated WS2 anode in a lithium half-cell configuration that showed a three-step charge–discharge behavior, characteristic of a conversion reaction. The electrochemical capacity was 118 mAh/g after 50 cycles.Keywords
This publication has 32 references indexed in Scilit:
- Tunable band gaps in bilayer transition-metal dichalcogenidesPhysical Review B, 2011
- Single-layer MoS2 transistorsNature Nanotechnology, 2011
- MoS2 and WS2 Analogues of GrapheneAngewandte Chemie, 2010
- Synthesis of WS2 nanosheets by a novel mechanical activation methodMaterials Letters, 2010
- Hydrogen storage using heterocyclic compounds: The hydrogenation of 2-methylthiopheneCatalysis Today, 2010
- Two‐Dimensional Nanosheet CrystalsAngewandte Chemie-International Edition, 2007
- Synthesis of tungsten disulfide (WS2) nanoflakes for lithium ion battery applicationElectrochemistry Communications, 2007
- Crystal Structures of Sulfides and Other ChalcogenidesReviews in Mineralogy and Geochemistry, 2006
- Solution-Processed Anodes from Layer-Structure Materials for High-Efficiency Polymer Light-Emitting DiodesJournal of the American Chemical Society, 2003
- The transition metal dichalcogenides discussion and interpretation of the observed optical, electrical and structural propertiesAdvances in Physics, 1969