Gao Guo, Zhang Qiang, Cheng Xin-Bing, Qiu Peiyu, Sun Rongjin, Yin Ting, Cui Daxiang
Institute of Nano Biomedicine and Engineering, Department of Instrument Science and Technology, Key Laboratory for Thin Film and Microfabrication Technology of Ministry of Education, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University , Shanghai 200240, China.
ACS Appl Mater Interfaces. 2015 Jan 14;7(1):340-50. doi: 10.1021/am506238q. Epub 2014 Dec 19.
In this work, we developed a facile hydrothermal method for synthesis of hybrid α-Fe2O3-carbon nanotubes (CNTs) architectures (α-Fe2O3-CNTs-1 and α-Fe2O3-CNTs-2). The CNTs are in situ attached to the α-Fe2O3 submicron spheres and form three-dimensional network robust architectures. The increase in the amount of CNTs in the network α-Fe2O3-CNTs architectures will significantly enhance the cycling and rate performance, as the flexible and robust CNTs could ensure the fast electron transport pathways, enhance the electronic conductivity, and improve the structural stability of the electrode. As for pure α-Fe2O3 submicron spheres, the capacity decreased significantly and retained at 377.4 mAh g(-1) after 11 cycles, and the capacity has a slightly increasing trend at the following cycling. In contrast, the network α-Fe2O3-CNTs-2 electrode shows the most remarkable performance. At the 60th cycle, the capacity of network α-Fe2O3-CNTs-2 (764.5 mAh g(-1)) is 1.78 times than that of α-Fe2O3 submicron spheres (428.3 mAh g(-1)). The long-term cycling performance (1000 cycles) of samples at a high current density of 5 C showed that the capacity of α-Fe2O3 submicron spheres fade to ∼37.3 mAh g(-1) at the 400th cycle and gradually increased to ∼116.7 mAh g(-1) at the 1000th cycle. The capacity of network α-Fe2O3-CNTs-2 maintained at ∼220.2 mAh g(-1) before the 400th cycle, arrived at ∼326.5 mAh g(-1) in the 615th, cycle and retained this value until 1000th cycle. The network α-Fe2O3-CNTs-2 composite could significantly enhance the cycling and rate performance than pure α-Fe2O3 submicron spheres composite.
在本工作中，我们开发了一种简便的水热法来合成杂化α-Fe₂O₃-碳纳米管（CNTs）结构（α-Fe₂O₃-CNTs-1和α-Fe₂O₃-CNTs-2）。碳纳米管原位附着在α-Fe₂O₃亚微米球上，并形成三维网络状坚固结构。网络状α-Fe₂O₃-CNTs结构中碳纳米管数量的增加将显著提高循环性能和倍率性能，因为柔性且坚固的碳纳米管能够确保快速的电子传输路径，提高电子导电性，并改善电极的结构稳定性。对于纯α-Fe₂O₃亚微米球，其容量显著下降，在11次循环后保持在377.4 mAh g⁻¹，并且在随后的循环中容量有略微上升趋势。相比之下，网络状α-Fe₂O₃-CNTs-2电极表现出最显著的性能。在第60次循环时，网络状α-Fe₂O₃-CNTs-2的容量（764.5 mAh g⁻¹）是α-Fe₂O₃亚微米球（428.3 mAh g⁻¹）的1.78倍。样品在5 C的高电流密度下的长期循环性能（1000次循环）表明，α-Fe₂O₃亚微米球的容量在第400次循环时降至约37.3 mAh g⁻¹，并在第1000次循环时逐渐增加至约116.7 mAh g⁻¹。网络状α-Fe₂O₃-CNTs-2的容量在第400次循环前保持在约220.2 mAh g⁻¹，在第615次循环时达到约326.5 mAh g⁻¹，并一直保持该值直至第1000次循环。与纯α-Fe₂O₃亚微米球复合材料相比，网络状α-Fe₂O₃-CNTs-2复合材料能够显著提高循环性能和倍率性能。
