Synthesis of α-Fe2O3 nanoparticles from Fe(OH)3 sol and their composite with reduced graphene oxide for lithium ion batteries

alpha-Fe2O3/reduced graphene oxide (alpha-Fe2O3/RGO) composite has been synthesized by a facile hydrothermal method. Fe(OH)(3) sol is creatively employed as the precursor and no nucleating agent is employed to help Fe3+ change to Fe(OH)(3). In the hydrothermal process, Fe(OH)(3) sol transforms to alpha-Fe2O3 particles and GO becomes RGO with hydrazine hydrate. Composites with different ratios between alpha-Fe2O3 and RGO for comparison are investigated as anode LIB materials. Among the composites, the alpha-Fe2O3/RGO containing 73% alpha-Fe2O3 exhibits the highest reversible specific capacity of similar to 950 mA h g(-1) after 70 cycles at a current density of 100 mA g(-1). When the current density is 800 mA g(-1), the capacity still remains as-700 mA h g(-1), showing superior rate capability. The significant electrochemical property improvements of alpha-Fe2O3/RGO can be attributed to the uniform alpha-Fe2O3 nanoparticles (20-30 nm) and the RGO substrate, which provides high electrical conductivity and stability.