Amorphous MoS ₃ -Coated ZnS Heterostructure with Interface-Enhanced Kinetics for Fast and Durable Sodium Storage via Multistep Reaction Pathways

The growing demand for advanced sodium-ion batteries (SIBs) necessitates the development of high-rate and durable anode materials. However, conventional ZnS-based anodes often suffer from sluggish ion transport kinetics and structural instability during cycling. Herein, a hierarchical ZnS/MoS₃ composite with a carbon matrix (ZSCM) was synthesized through a MOF-derived carbonization-sulfurization route followed by an amorphous MoS₃ surface modification. This unique architecture combines a conductive 3D carbon framework, abundant heterointerfaces, and multiphase synergy, which significantly enhance charge transport and interfacial reaction kinetics. As a result, the ZSCM anode delivers a high reversible capacity of 559.3 mAh·g^-1 at 0.1 A·g^-1 and maintains 370.8 mAh·g^-1 even at 10 A·g^-1. Structural and spectroscopic analyses reveal a multistep sodium storage mechanism involving the irreversible conversion and partial alloying of ZnS, along with the stepwise reduction and partial reoxidation of MoS₃. Moreover, the ZnS/MoS₃ heterointerface induces a built-in electric field due to interfacial work function differences, which facilitates charge redistribution and accelerates ion/electron migration. The assembled full cell with Na₃V₂(PO₄)₃ as the cathode further confirms the practical applicability of this design. This work offers mechanistic insights and an effective strategy for constructing ZnS-based anodes toward high-performance, multistep sodium storage.