Covalently bridged bond assembly of MoS2lamellae onto a graphene sheet: an outstanding electrode for high rate and long-life lithium/sodium-ion batteries

Mengyuan Guo; Huipei Zhang; Luyao Qi; Shan Zhang; Yanmin Qin; Binglu Deng

doi:10.1088/1361-6528/acfaa4

Covalently bridged bond assembly of MoS₂lamellae onto a graphene sheet: an outstanding electrode for high rate and long-life lithium/sodium-ion batteries

Nanotechnology. 2023 Oct 4;34(50). doi: 10.1088/1361-6528/acfaa4.

Authors

Mengyuan Guo¹, Huipei Zhang¹, Luyao Qi¹, Shan Zhang¹, Yanmin Qin¹, Binglu Deng²

Affiliations

¹ State Key Laboratory Cultivation Base for New Textile Materials and Advanced Processing Technology, School of Materials Science and Engineering, Wuhan Textile University, Wuhan 430200, People's Republic of China.
² School of Materials Science and Hydrogen Energy, Foshan University, Foshan, 528231, People's Republic of China.

PMID: 37789673
DOI: 10.1088/1361-6528/acfaa4

Abstract

The practical application of Molybdenum sulphide (MoS₂) electrodes has been hindered by its structural instability, and poor electrical conductivity. To enhance the cycle stability and rate performance of MoS₂in lithium/sodium-ion batteries (LIBs/SIBs), we synthesized a graphene-supported MoS₂composite (MoS₂@rGO) with affluent covalent bridged bonds through a facile and scalable hydrothermal and annealing process. The covalent bridged bonds of Mo-S-C, Mo-O-C and C-O-S provide an effective charge transfer path between MoS₂and graphene, facilitating fast charge hopping and improving rate performance. As anode materials for LIBs, the MoS₂@rGO exhibited exceptional long-term cycle life (906 mAh g^-1at 1.0 A g^-1after 400 cycles) and outstanding rate capability (1267.7/314.7 mAh g^-1at 0.1/6.5 A g^-1). Additionally, the MoS₂@rGO electrode demonstrated a stable reversible capacity of 521.7 mAh g^-1at 1.0 A g^-1after 700 cycles and excellent rate capabilities of 665.1 and 326.3 mAh g^-1at 0.1 and 10.0 A g^-1in SIBs. The edge Mo of MoS₂is directly coupled with the oxygen of the functional group on rGO, achieved by adjusting the pH value of the solution to tune the surface charge feature, can effectively enhance the structural stability of electrode even under higher current density.

Keywords: MoS2; covalent bridged bonds; cycle stability; high-rate performances; lithium/sodium-ion batteries.