FeS₂@Porous octahedral carbon derived from metal-organic framework as a stable and high capacity anode for lithium-ion batteries

A facile approach that combines the chemical etching with sulfidation of the sacrificial templates of the Fe-based MOFs is developed to prepare FeS₂@ Porous Octahedral Carbon (FeS₂@POC). The porous carbon shell can improve the conductivity of active materials, bring a high reversible capacity. Moreover, the void space between carbon and FeS₂ can accommodate the volume changes during cycling and the existence of carbon can prevent the aggregation of pulverized FeS₂ particles during Li ions insertion/extraction process, which are favorable to gain superior cycling stability. When used as an anode for lithium-ion batteries, the FeS₂@POC shows superior electrochemical performance with a high specific capacity, excellent rate performance (381 mAh g⁻¹ at 5000 mA g⁻¹) and good cyclability (1074 mAh g⁻¹ at 100 mA g⁻¹ after 100 cycles, about 99% capacity retention). The results demonstrate that this product may be considered as a promising anode material for advanced lithium-ion batteries.