Bimetallic sulfide anodes based on heterojunction structures for high-performance sodium-ion battery anodes

Bimetallic sulfide anodes offer promising stability and high capacity in sodium-ion batteries (SIBs) but face significant challenges, including low electronic conductivity, limited ionic diffusion, and substantial volume expansion during conversion and alloying processes. These issues significantly impair the performance. To effectively address these challenges, we employed a systematic design approach to develop a bimetallic ZnS/MoS2 hierarchical heterostructure coated with nitrogen-doped carbon (T-MS/C). This advanced structure was synthesized using a metal-organic framework (MOF) as a template, followed by hydrothermal synthesis. The resulting heterostructure features multiple layers arranged hierarchically, incorporating various phase interfaces and smaller crystal domains due to the MOF templating process. This design significantly enhances reactivity, electrical conductivity, and ionic diffusion, ultimately leading to the development of an optimized Na-storage performance T-MS/C anode. The T-MS/C anode exhibits remarkable Na-storage capability, with capacities of 690.8 mAh/g after 100 cycles at 0.2 A/g and 306 mAh/g at 10 A/g. This carefully synthesized T-MS/C anode exhibits highly promising features for Na-storage, making it an excellent contender for the next generation of high-performance SIBs. The multilayered heterostructure configuration provides several active sites while also facilitating rapid ion diffusion. Incorporating a carbon layer creates an efficient buffering matrix, effectively minimizing the occurrence of ZnS and MoS2 agglomeration. The as-prepared ZnS/MoS2@NC anode has remarkable Na-storage performance, with capacities of 690.8 mAh/g at 0.2 A/g after 100 cycles and 306 mAh/g at a high current density of 10 A/g. [Display omitted]