Data from: Exfoliated transition metal dichalcogenide nanosheets for supercapacitor and sodium ion battery applications
Mukherjee, Santanu et al. (2019), Data from: Exfoliated transition metal dichalcogenide nanosheets for supercapacitor and sodium ion battery applications, Dryad, Dataset, https://doi.org/10.5061/dryad.tv2tk65
Growing concerns regarding the safety, flammability, and hazards posed by Li-ion systems have led to research on alternative rechargeable metal-ion electrochemical storage technologies. Among the most notable of these are Na-ion supercapacitors and batteries, motivated in part because of the similar size and electrochemistry of Li and Na ions. However, sodium ion batteries (SIBs) come with their own set of issues, especially the large size of the Na+ ion, its relatively sluggish kinetics and low energy densities. This makes the development of novel materials and appropriate electrode architecture is of absolute significance. Transition metal dichalcogenides (TMDs), in this regard have attracted a lot of attention due of their relative ease of exfoliation, diverse morphologies and architectures with superior electronic properties. Here, we study the electrochemical performance of Mo based two dimensional (2D) layered TMDs (e.g. MoS2, MoSe2, and MoTe2), exfoliated in a superacid, for battery and supercapacitor applications. The exfoliated TMD flakes were interfaced with reduced graphene oxide (rGO) to be used as composite electrodes. Electron microscopy, elemental mapping, Raman spectra were used to analyze the exfoliated material and confirm the formation of 2D TMD/rGO layer morphology. For supercapacitor applications in aqueous media, the sulfide-based TMD (MoS2) exhibited the best performance, providing an areal capacitance of 60.25 mF cm-2. For SIB applications, TMD electrodes exhibited significantly high charge capacities than the neat rGO electrode. The initial desodiation capacities for the composite electrodes 468.84 mAh g-1 (1687.82 C g-1), 399.10 mAh g-1 (1436.76 C g-1) and 387.36 mAh g-1 (1394.49 C g-1) for MoS2, MoSe2, and MoTe2 respectively. Also, all the composite TMD electrodes provided a coulombic efficiency of ∼100 % after few cycles.
National Science Foundation, Award: 1454151