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

α-Fe2O3/reduced graphene oxide (α-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 α-Fe2O3 particles and GO becomes RGO with hydrazine hydrate. Composites with different ratios between α-Fe2O3 and RGO for comparison are investigated as anode LIB materials. Among the composites, the α-Fe2O3/RGO containing 73% α-Fe2O3 exhibits the highest reversible specific capacity of ∼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 α-Fe2O3/RGO can be attributed to the uniform α-Fe2O3 nanoparticles (20–30 nm) and the RGO substrate, which provides high electrical conductivity and stability.