Sn/Co-MOF-Derived Ultrafine Heterostructure SnS ₂ /CoS ₂ @SC as Anode Materials for Lithium-Ion Batteries

High-performance anode materials are crucial for advancing lithium-ion battery (LIB) technologies, yet challenges such as limited capacity, poor rate capability, and structural degradation during cycling remain unresolved. In this study, a cubic bimetallic organic framework (Sn/Co-MOF) is synthesized via a room-temperature self-assembly method and employed as a precursor to construct an ultrafine nanoheterostructure SnS2/CoS2@SC composite. The sulfur-doped carbon (S-doped C) backbone not only promotes electrical conductivity to enable effective electron transport but also, through its internal hollow structure, accommodates volume expansion, thereby maintaining structural integrity throughout charge–discharge cycles. The construction of an ultrafine SnS2/CoS2 heterostructure markedly enhances electrochemical behavior by increasing the effective electrode–electrolyte interface, reducing Li+ transport distances, and promoting rapid ionic diffusion. In addition, the cooperative effect between SnS2 and CoS2 mitigates localized stress accumulation, thereby suppressing structural degradation and enabling durable cycling performance. Consequently, the SnS2/CoS2@SC electrode retains a high capacity with good reversibility of 1154.6 mAh g–1 after 500 cycles at 0.2 A g–1, and still delivers 854.5 mAh g–1 after 1000 cycles at 2.0 A g–1. Collectively, the SnS2/CoS2@SC composite emerges as a promising anode material for lithium-ion batteries, delivering high capacity, outstanding rate performance, and long-term structural robustness suitable for advanced energy storage technologies.