Hierarchical nanostructured FeS2 hollow microspheres for lithium-ion batteries

The hierarchical nanostructured FeS2 hollow microspheres composed of nanoflakes were fabricated based on Ostwald ripening using sulfur powder as sulfur source and triethanolamine as both solvent and reducing agent, and electrochemically investigated as cathode material for lithium-ion batteries. The as-obtained FeS2 electrode delivered an initial capacity of 886.3 mA h g(-1) at 0.1 C at ambient temperature, which is one of the highest values in the reported results. In the subsequent cycles following the first cycle, the electrode exhibited good reversibility at ambient temperature, resulting in good cycling stability and performance, and the discharge capacity of 392.7 mA h g(-1) at 1 C was still retained after 30 cycles. This might be attributed to the unique FeS2 structure with hierarchical nanostructured hollow microspheres, showing potential to develop FeS2 cathode materials with high energy density for lithium-ion batteries.