Self-assembled FeS2 cubes anchored on reduced graphene oxide as an anode material for lithium ion batteries

A novel composite of reduced graphene oxide (RGO) and FeS2 microparticles self-assembled from small size cubes as a high-performance anode material for lithium-ion batteries (LIBs) has been prepared via a facile one-pot hydrothermal method. The prepared composite shows interconnected networks of reduced graphene oxide sheets and well-dispersed FeS2 microparticles which were composed of small-size cubic FeS2 crystals. The composite not only provides a high contact area between the electrolyte and the electrode, favorable diffusion kinetics for both electrons and lithium ions, but also provides the protection against the volume changes of electroactive FeS2 materials and excellent electrical conductivity of the overall electrode during electrochemical processes as well as an enhanced synergistic effect between cubic FeS2 and RGO. As an anode material for LIBs, it exhibits a very large initial reversible capacity of 1147 mA h g(-1) at a current rate of 100 mA h g(-1) and maintains 1001.41 mA h g(-1) over 60 cycles, which is much higher than that of the theoretical capacity of graphite (372 mA h g(-1)) and indicates high stability. The results demonstrate that the composite can be a promising candidate for electroactive materials in LIBs.