Engineering defect‐enabled 3D porous MoS₂/C architectures for high performance lithium‐ion batteries

Abstract

Designing defect‐rich MoS2/C architectures with three‐dimensional (3D) porous frame effectively improve the electrochemical performance of lithium‐ion batteries (LIBs) owing to the improved conductivity and decreased diffusion distance of Li+ ions for lithium storage. Herein, we report a reliable morphology engineering method combining with tunable defects to synthesize defect‐rich MoS2 nanosheets with a few layers entrapped carbon sheath, forming a 3D porous conductive network architecture. The defect‐rich MoS2 nanosheets with expanded interlayers can provide a shortened ion diffusion path, and realize the 3D Li+ diffusion with faster kinetics. A 3D conductive interconnected carbon network is able to improve interparticle conductivity, concurrently maintaining the structural integrity. Benefiting from these intriguing features, the as‐prepared MoS2/C architectures exhibit excellent electrochemical performance: a high reversible capacity of 1163 mAh g−1 at a current density of 0.1 A g−1 after 100 cycles and a high rate capability of 800 mAh g−1 at 5 A g−1. Defect content in MoS2/C architectures can be obtained by changing H2 concentration. Compared with the counterparts with few defects, the defect‐rich MoS2/C architectures show improved electrochemical stability with a superior cycle life, illustrating a highly reversible capacity of 751 mAh g−1 at 0.5 A g−1 after 500 cycles.

Vertically Stacked 2H‐1T Dual‐Phase MoS2 Microstructures during Lithium Intercalation: A First Principles Study

“…Layered transition‐metal dichalcogenides (TMDs) offer a high density of electrochemically active sites, fast ion transport, and hence, can lead to improved theoretical capacity and cycling stability of LIBs 17‐19 . The large surface area and weak out‐of‐plane van der Waals (vdW) interactions in these materials, can overcome the current challenges of poor electronic conductivity and damaging volumetric fluctuations during the intercalation and de‐intercalation.…”

Investigation the sodium storage kinetics of H1.07Ti1.73O4@rGO composites for high rate and long cycle performance

“…As 2D reduced graphene oxide (rGO) nanosheets not only can improve the charge transfer speed but also prevents agglomeration of the composites during the multiple sodiation/ desodiation cycles. [43][44][45][46] Moreover, rGO can further improve the surface kinetics of HTO. 47,48 In this work, HTO@rGO composites were synthesized by a simple electrostatic assembly process followed by hydrothermal treatment, and exhibited an excellent electrochemical performance, including high rate capability and long cycle stability.…”

“…As 2D reduced graphene oxide (rGO) nanosheets not only can improve the charge transfer speed but also prevents agglomeration of the composites during the multiple sodiation/desodiation cycles 43–46 . Moreover, rGO can further improve the surface kinetics of HTO 47,48 .…”

Function and Application of Defect Chemistry in High‐Capacity Electrode Materials for Li‐Based Batteries

“…Once a vacancy is generated, an interstitial defect is generated at the new location or the disappearance of the oppositely charged ions [7] . In particular, the anionic O and S vacancies have been widely reported as the functional sites in various materials (such as TiO 2 , [8] WO, [9] and MoS 2 [10] ) for improving their electrochemical performance. Our group has introduced the cathodic Li vacancies by a solid‐state method and verified their functional sites in LRMC cathode materials [5] …”