Engineering of electrolyte ion channels in MXene/holey graphene electrodes for superior supercapacitive performances
Engineering of electrolyte ion channels in MXene/holey graphene electrodes for superior supercapacitive performances
复制标题
MXene/多孔石墨烯电极中的电解质离子通道工程可实现卓越的超级电容性能
DOI：
10.1007/s12598-021-01935-6
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发表时间：
2022
期刊：
影响因子：
8.8
通讯作者：
Xuyuan Chen
中科院分区：
文献类型：
--
作者：
Zhuo Cai;Yifei Ma;Mei Wang;Aniu Qian;Zhaomin Tong;Liantuan Xiao;Suotang Jia;Xuyuan Chen
MXene由于其高导电性和氧化还原性，在超级电容器电极材料中有着广阔的应用前景。然而，MXene片层的自团聚会减少其与电解质的接触面积，使电解质离子的运输路径曲折，从而降低其电容性能和倍率能力。在这项工作中，我们通过调整MXene片层尺寸并将多孔石墨烯（HG）纳米片插入MXene片层的中间层来设计电解质离子通道。所开发的MXene/HG电极不仅可以避免MXene的自堆积，而且可以提供畅通的离子传输通道。结果表明，基于MXene薄片的小型MXene/HG （S-MXene/HG）超级电容器的超电容性能和速率性能得到了显著改善。通过调整HG的含量，S-MXene/ hg0.05电极的重量电容为446 F·g−1，倍率容量为77.5%。基于S-MXene/ hg0.05的对称超级电容器提供了令人印象深刻的能量密度14.84 Wh·kg - 1，具有优异的循环稳定性，在10,000次循环后保持96%的电容。离子通道工程的演示显示了基于二维材料的超级电容器电极的巨大潜力。图形抽象
MXene has given great promises to supercapacitor electrode material due to its high conductivity and redox properties. However, the self-agglomeration of the MXene lamella will reduce its contact area with the electrolyte and generate a tortuous transportation pathway of the electrolyte ions, thereby reducing its capacitive performance and rate capability. In this work, we engineered the electrolyte ion channels by adjusting the MXene lamella size and inserting holey graphene (HG) nanosheets into the interlayer of the MXene flakes. The developed MXene/HG electrode can not only avoid the self-restacking of MXene but also provide unimpeded ion transport channels. As a result, the supercapacitive and rate performances of the small MXene lamella-based MXene/HG (S-MXene/HG) supercapacitor are prominently ameliorated. By adjusting the content of HG, the S-MXene/HG0.05electrode exhibits excellent gravimetric capacitance of 446 F·g−1and a rate capability of 77.5%. The S-MXene/HG0.05-based symmetric supercapacitor provides an impressive energy density of 14.84 Wh·kg−1with excellent cyclic stability of 96% capacitance retention after 10,000 cycles. This demonstration of the engineering of the ion channels shows great potential in two-dimensional material-based supercapacitor electrodes.Graphical abstract