Qian Yong, Jiang Song, Li Yang, Yi Zheng, Zhou Jie, Tian Jie, Lin Ning, Qian Yitai
Hefei National Laboratory for Physical Sciences at the Microscale, Department of Applied Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China.
Experiment Center of Engineering and Material Science, University of Science and Technology of China, Hefei, 230026, P. R. China.
Angew Chem Int Ed Engl. 2019 Dec 9;58(50):18108-18115. doi: 10.1002/anie.201912287. Epub 2019 Oct 24.
A highly oriented mesoporous graphitic carbon nanospring (OGCS) with graphitic layers that are perpendicular to the axis is prepared by hydrothermal treatment of epoxy resin at 500 °C and annealing at 1400 °C. Water plays an important role in not only forming the graphitic carbon nanospring with a high [002] orientation and a large amount of active edge-plane sites, but also in the generation of the mesoporous structure, which facilitate fast K-ion adsorption and diffusion. In situ and ex situ measurements confirm that OGCS undergoes K-adsorption in mesopores and then K-intercalation in the graphite layer to form KC with a low discharge voltage. The spring-like nanostructure can expand one-dimensionally along the axial direction to accommodate the volume variation. The OGCS electrode thus shows a much better K-storage performance than that of unoriented graphitic carbon.
通过在500°C下对环氧树脂进行水热处理并在1400°C下退火，制备了一种具有垂直于轴的石墨层的高度取向介孔石墨碳纳米弹簧（OGCS）。水不仅在形成具有高[002]取向和大量活性边缘平面位点的石墨碳纳米弹簧中起着重要作用，而且在介孔结构的生成中也起着重要作用，这有利于快速的钾离子吸附和扩散。原位和非原位测量证实，OGCS在介孔中发生钾吸附，然后在石墨层中发生钾嵌入，以形成具有低放电电压的KC。弹簧状纳米结构可以沿轴向一维扩展以适应体积变化。因此，OGCS电极显示出比无取向石墨碳更好的钾存储性能。
