Improved Electrochemical Performance of NTs-WS₂@C Nanocomposites for Lithium-Ion and Sodium-Ion Batteries

Abstract

Even though WS2 nanotubes (NTs-WS2) have great potential as anode materials for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) thanks to their unusual layered structure, their conductivity and cycling stability are far from satisfactory. To tackle these issues, carbon-coated WS2 (NTs-WS2@C) nanocomposites were prepared through a facile synthesis method that involved precipitating a carbon precursor (20% sucrose) on WS2 nanotubes, followed by annealing treatment under an argon environment. Thanks to the presence of highly conductive and mechanically robust carbon on the outer surface, NTs-WS2@C nanocomposites show improved electrochemical performance compared with bare NTs-WS2. After 60 cycles at 80 mA g–1 current density, the cells display high capacities of 305 mAh g–1 in LIBs and 152 mAh g–1 in SIBs, respectively. As the current density increases to 600 mA g–1, it provides specific capacities of 209 and 115 mAh g–1, correspondingly. The enhanced electrochemical performance in LIBs and SIBs is primarily attributed to the synergistic effects of the tubular architecture of WS2, carbon network and stable nanocomposite structure, which can effectively constrain volume variation during the metal ions intercalation/deintercalation processes.

Silane functionalization of WS2 nanotubes for interaction with poly(lactic acid)

“…This temperature range was chosen assuming residual APTES was removed below 200 °C. Knowing the specific surface area (SSA BET ) of the WS 2 NTs, 59 from BET measurements = 19.19 m 2 g −1 the coverage density ( σ ) can be readily calculated using eqn (3) and the values are listed in Table 1:…”

A Novel Hierarchical Structure of SnCu2Se4/d-Ti3C2Tx/NPC for a Lithium/Sodium Ion Battery and Hybrid Capacitor with Long-Term Cycling Stabilities

“…The GCD profiles of SnCu 2 Se 4 /d-Ti 3 C 2 T x /NPC are presented in Figure b at 0.1 A g –1 , which deliver initial discharge and charge capacities of 780 and 609 mAh g –1 , respectively. The low initial coulombic efficiency (CE) of 78% may be attributed to the decomposition of the electrolyte and the formation of a solid electrolyte interface (SEI) film. − The CEs improve to 94 and 96% in the following second and third cycles, respectively, suggesting the good reversibility of the SnCu 2 Se 4 /d-Ti 3 C 2 T x /NPC anode for Li + insertion/extraction.…”

WS2 Nanotube-Embedded SiOC Fibermat Electrodes for Sodium-Ion Batteries

“…For alleviating the aforementioned deleterious properties, heterostructures of WS 2 NTs and carbon have been utilized in a recent study, where an improvement in the electrochemical properties of WS 2 NTs were observed. The investigation led by Zdeněk and co-workers showed that the NTs-WS 2 @C composite electrode sustained a capacity of 152 mA h g –1 after 60 cycles when tested at a current density of 80 mA g –1 in a sodium ion half-cell . However, such a capacity is insufficient to fulfill the need for application in modern technological devices.…”

“…The investigation led by Zdeněk and co-workers showed that the NTs-WS 2 @C composite electrode sustained a capacity of 152 mA h g –1 after 60 cycles when tested at a current density of 80 mA g –1 in a sodium ion half-cell. 21 However, such a capacity is insufficient to fulfill the need for application in modern technological devices. An alternative hybridization method to minimize the shortcomings of TMD-based 1D structures is to functionalize them with polymer-derived ceramic materials (PDCs).…”