石墨烯包裹的爆米花中空结构的FeS纳米颗粒作为钠离子电池阳极的性能研究

Popcorn-structured hollow FeS nanoparticles wrapped in reduced graphene oxide as high-performance sodium-ion battery anodes

用一步水热法合成多孔的爆米花形状的由还原石墨烯包裹的FeS纳米颗粒,该复合颗粒作为钠离子电池阳极使用.多孔结构因为大的表面积有助于该复合物展现出优越的循环稳定性和速率性能.在电流密度为100 mA g-1时,100次循环之后该复合物依然保持可逆比容量为552 mA h g-1;在电流密度为5000 mA g-1时,表现出比容量为307 mA h g-1.此外,Na, S和Fe的相图分析揭露了Na和FeS在充放电过程中的氧化还原机制.

Popcorn-structured hollow FeS nanoparticles wrapped by reduced graphene oxide are synthesized by a facile one-step solvothermal approach and applied as sodium-ion battery anodes. Porous structure helps this composite to exhibit a superior cycling stability and rate performance, when it is used for sodium storage, this composite keeps a reversible capacity of 552 mA h g-1 after 100 cycles at a current density of 100 mA g-1, and shows impressive rate performance with a capacity of 307 mA h g-1 at current densities of 5000 mA g-1, respectively. Additionally, the phase diagram of Na, S and Fe is calculated to investigate the mechanisms for reduction and oxidation of sodium and FeS during discharge/charge.