Nitrogen-doped mesoporous carbon of extraordinary capacitance for electrochemical energy storage
Nitrogen-doped mesoporous carbon of extraordinary capacitance for electrochemical energy storage
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用于电化学储能的具有非凡电容的氮掺杂介孔碳
DOI：
10.1126/science.aab3798
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发表时间：
2015-12-18
期刊：
影响因子：
56.9
通讯作者：
Huang, Fuqiang
中科院分区：
文献类型：
--
作者：
Lin, Tianquan;Chen, I-Wei;Huang, Fuqiang
与电池相比，电容器通常可以存储更少的电力，但它们可以更快地捕获和释放电力。Lin等人制造了一种多孔碳材料，然后用氮掺杂。这将碳的能量密度提高了三倍多，而这种提高在全电容器中得以保留，同时又不会失去快速供电的能力。高能量和功率密度被封装到氮掺杂的有序介孔导电碳超级电容器中。碳基超级电容器可以提供高电力，但它们没有足够的能量密度来直接与电池竞争。我们发现，氮掺杂的有序介孔少层碳在水性电解质中的电容为855法拉/克，并且可以以快速的碳样速度进行双极充电或放电。这种改进主要源于氮相关缺陷处的强氧化还原反应，该反应将惰性石墨烯状层状碳转化为电化学活性物质，而不影响其导电性。这些双极水电解质电化学电池提供与碳基超级电容器相似的功率密度和寿命，并且可以存储每千克41瓦时（每升19.5瓦时）的比能量。
Store more energy with a touch of nitrogen In contrast to batteries, capacitors typically can store less power, but they can capture and release that power much more quickly. Lin et al. fabricated a porous carbon material that was then doped with nitrogen. This raised the energy density of the carbon more than threefold—an increase that was retained in full capacitors, without losing their ability to deliver power quickly. Science, this issue p. 1508 High energy and power density are packed into nitrogen-doped, ordered mesoporous conductive carbon supercapacitors. Carbon-based supercapacitors can provide high electrical power, but they do not have sufficient energy density to directly compete with batteries. We found that a nitrogen-doped ordered mesoporous few-layer carbon has a capacitance of 855 farads per gram in aqueous electrolytes and can be bipolarly charged or discharged at a fast, carbon-like speed. The improvement mostly stems from robust redox reactions at nitrogen-associated defects that transform inert graphene-like layered carbon into an electrochemically active substance without affecting its electric conductivity. These bipolar aqueous-electrolyte electrochemical cells offer power densities and lifetimes similar to those of carbon-based supercapacitors and can store a specific energy of 41 watt-hours per kilogram (19.5 watt-hours per liter).