Electrochemical charge storage in hierarchical carbon manifolds
Electrochemical charge storage in hierarchical carbon manifolds
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DOI：
10.1016/j.carbon.2015.11.078
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发表时间：
2016-04
期刊：
影响因子：
10.9
通讯作者：
R. Narayanan;H. Vijwani;S. Mukhopadhyay;P. Bandaru
中科院分区：
文献类型：
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作者：
R. Narayanan;H. Vijwani;S. Mukhopadhyay;P. Bandaru
建议使用由大孔结构(例如，网状玻璃碳，RVC)构成的分层组件，其中内部孔区被紧密间隔的纳米结构(例如，碳纳米管，CNT)覆盖，以显著提高电化学电容器的能量密度，同时保持较大的充放电速率。虽然宏孔能够存储大量的电解液体积，这些体积将通过氧化还原反应对能量密度做出贡献，但紧密分隔的纳米结构除了能够通过薄层电化学(TLE)实现与速率无关的法拉第电荷存储外，还提供了大的几何面积和电容。与裸RVC泡沫电极相比，RVC-CNT电极的双层电容增加了50倍，法拉第电荷密度也增加了几个数量级。结果表明，这种分级组装使得∼能够贡献润湿的RVC-碳纳米管电极94%的体积，用于有源法拉第电荷存储。
The use of hierarchical assemblies constituted from macroporous structures (e.g.,reticulated vitreous carbon, RVC) where the internal pore area is covered with closely spaced nanostructures (e.g.,carbon nanotubes, CNT) is proposed for substantially enhancing the energy density of electrochemical capacitors, while maintaining large charge/discharge rates. While the macroscale pores enable storage of substantial electrolyte volumes that would contribute through redox reactions to the energy density, the closely spaced nanostructures provide a large geometric area and capacitance in addition to enabling rate independent Faradaic charge storage via thin layer electrochemistry (TLE). A fifty fold increase in the double layer capacitance, in addition to increased Faradaic charge density – with potential for orders of magnitude improvement, was observed for the RVC-CNT electrodes, in comparison to the bare RVC foam electrode. It was seen that the hierarchical assembly enables the contribution from ∼94% of thenetvolume of the wetted RVC-CNT electrode for active Faradaic charge storage.