Electrospun α-Fe2O3 nanorods as a stable, high capacity anode material for Li-ion batteries

Abstract

α-Fe2O3 nanorods are synthesized by electrospinning of polyvinylpyrrolidone (PVP)/ferric acetyl acetonate (Fe(acac)3) composite precursors and subsequent annealing at 500 °C for 5 h. X-ray diffraction and Raman spectroscopy analyses confirm the formation of a hematite structure as the predominant phase. The electron microscopy studies show that the electrospun α-Fe2O3 nanorods are composed of agglomerates of nano-sized particles and the average diameter of the nanorods is found to be 150 nm. Li-storage and cycling properties are examined by galvanostatic cycling in the voltage range 0.005–3 V vs. Li at various current densities and it is complemented by cyclic voltammetry. The electrospun α-Fe2O3 nanorods exhibit a high reversible capacity of 1095 mA h g−1 at 0.05 C, are stable up to 50 cycles and also show high rate capability, up to 2.5 C. The high rate capability and excellent cycling stability can be attributed to the unique morphology of the macroporous nanorods comprised of inter-connected nano-sized particles, thus making electrospun α-Fe2O3 a promising anode material for Li-ion batteries.