Department of Mechanical Engineering, University of Delaware , Newark, Delaware 19716, United States.
ACS Appl Mater Interfaces. 2013 Oct 23;5(20):10246-52. doi: 10.1021/am403028z. Epub 2013 Oct 1.
A facile and effective hydrogen annealing method has been demonstrated to synthesize iron oxide/SWNT hybrid films involving the thermal reduction of rhombohedral Fe2O3 to cubic Fe3O4 through the phase transformation while maintaining the morphological integrity of the films. The poor rate capability and cyclic stability of the original α-Fe2O3/SWNT hybrid films have been significantly improved by H2 annealing. The prepared iron oxide/SWNT hybrid films have a high capacity of 786 mA h g(-1) at a high current density of 4 A g(-1) with a prolonged lifetime. The enhancement of the electrochemical performance is attributed to the presence of highly conductive Fe3O4, accelerated charge-transfer kinetics, and the increased Li+ diffusivity confirmed by electrochemical impedance spectra and galvanostatic intermittent titration.
一种简便有效的氢气退火方法被证明可以合成氧化铁/单壁碳纳米管（SWNT）混合薄膜，该方法涉及通过相变将菱面体 Fe2O3 热还原为立方相 Fe3O4，同时保持薄膜的形态完整性。通过氢气退火，显著提高了原始α-Fe2O3/SWNT 混合薄膜的倍率性能和循环稳定性。所制备的氧化铁/SWNT 混合薄膜在 4 A g-1 的高电流密度下具有高达 786 mA h g-1 的高容量和长循环寿命。电化学性能的增强归因于高导电性 Fe3O4 的存在，加速了电荷转移动力学，以及通过电化学阻抗谱和恒电流间歇滴定法证实的 Li+扩散率的提高。
