Applied Surface Science, Vol.375, 101-109, 2016
Improved electrochemical performance of alpha-Fe2O3 nanorods and nanotubes confined in carbon nanoshells
Core-shell alpha-Fe2O3@C nanorods (FC1) and nanotubes (FC2) are synthesized via a hydrothermal method with further annealing. The structure, morphology and lithium storage performance are investigated by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, thermogravimetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy. The electrode based on the core-shell nanotubes (FC2) delivers the reversible capacity of 1350 mAh g(-1) cycled at 100 mA g(-1) after 50 cycles, 1186 mAh g-1 at 500 mA g(-1) after 100 cycles, and 765 mAh g(-1) at 2 A g-1 after 300 cycles, much higher than those of pure alpha-Fe2O3 nanotubes and the core-shell nanorods (FC1). Electrochemical measurements show that the tubular morphology and the carbon shell play an important role in affecting both the cycle life and the rate capability of the electrodes. These insights will be of benefits in designing of other anode materials for lithium-ion batteries. (C) 2016 Elsevier B.V. All rights reserved.