A team from the University of Wollongong (Australia) and the University of Technology, Sydney reported the successful synthesis by a simple hydrothermal approach of high-capacity WS2 (tungsten disulfide)@graphene nanocomposite anodes for sodium-ion batteries. Their paper is published in the RSC journal Chemical Communications.
|Schematic diagram of the WS2@graphene nanocomposites. Su et al. Click to enlarge.|
XRD, FESEM, and TEM analyses of the prepared material showed that the WS2 nanocrystals were homogeneously distributed on the graphene nanosheets.
Anodes were prepared by dispersing 70 wt. % as-prepared materials, 20 wt. % acetylene carbon black, and 10 wt. % PVDF binder in N-methyl-2-pyrrolidone (NMP) to form a slurry. The resultant slurry was pasted onto copper foil using a doctor blade and dried in a vacuum oven for 12 h, which was followed by pressing at 200 kg cm-2. The typical loading of each electrode was approximately 1.2 mg cm-2.
Electrochemical measurements were carried out using two-electrode coin cells (CR2032) with Na metal as reference and counter electrode and glass microfiber as the separator.
… the WS2@graphene nanocomposite showed its highly reactive nature towards sodium storage. It demonstrated a high reversible specific capacity of about 594 mA h g-1, excellent cyclability, and a good high rate performance, which could be ascribed to the highly conductive graphene matrix and the unique 3D architecture of the nanocomposite. WS2@graphene nanocomposite is a promising high performance anode material for Na-ion batteries.—Su et al.
Dawei Su, Shi Xue Dou and Guoxiu Wang (2014) “WS2@graphene Nanocomposites as Anode Materials for Na-ion Batteries with Enhanced Electrochemical Performances” Chem. Commun. doi: 10.1039/C4CC00840E