Rational design of MWCNTs@amorphous carbon@MoS2: Towards high performance cathode for aqueous zinc-ion batteries.

[Display omitted] • MWCNTs@a-C@MoS 2 with large interlayer and fast kinetics was synthesized. • Amorphous carbon provides necessary conditions for uniform growth of MoS 2. • The optimized material has excellent cycle stability and rate performance. • The flexible quasi-solid-state AZIB has stable properties at extreme bending states. The sluggish diffusion kinetics of divalent Zn2+ in cathode and the limited availability of active material have seriously hindered the practical application of aqueous zinc ion batteries (AZIBs). Herein, multi-walled carbon nanotubes modified by amorphous carbon layer successfully compounded with MoS 2 (MWCNTs@a-C@MoS 2) are designed as the cathode for AZIBs. Benefiting from the large number of oxygenous groups on the loose surface of amorphous carbon, MoS 2 can uniformly nucleate and grow on the MWCNTs, thus avoiding the agglomeration of MoS 2 and improving the utilization of active materials. Therefore, this nanocomposite exhibits long-term cycling stability (78% capacity retention after 1000 cycles at 5 A g-1) and glorious high-rate capability (110 mAh g-1 at 12 A g-1). The electrochemical reaction kinetics of MWCNTs@a-C@MoS 2 electrode were investigated by galvanostatic intermittent titration (GITT), cyclic voltammetry (CV) measurements and molecular dynamics (MD) simulations, indicating its desirable pseudocapacitive behaviors and low Zn2+ diffusion energy barrier. By ex-situ characterizations, the Zn-intercalation mechanism of MWCNTs@a-C@MoS 2 was revealed. This electrode also exhibits stable performance in flexible quasi-solid-state AZIBs even under extreme bending conditions, demonstrating its practicality. [ABSTRACT FROM AUTHOR]