Ma Hongyun, Geng Hongya, Yao Bowen, Wu Mingmao, Li Chun, Zhang Miao, Chi Fengyao, Qu Liangti
MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry , Tsinghua University , Beijing 100084 , People's Republic of China.
Key Laboratory for Advanced Materials Processing Technology, Ministry of Education of China, and State Key Laboratory of Tribology, Department of Mechanical Engineering , Tsinghua University , Beijing 100084 , People's Republic of China.
ACS Nano. 2019 Aug 27;13(8):9161-9170. doi: 10.1021/acsnano.9b03492. Epub 2019 Jul 22.
As an emerging type of electrochemical energy storage devices, sodium-ion capacitors (SICs) are potentially capable of high energy density and high power density, as well as low cost and long lifespan. Unfortunately, the lack of high-performance capacitive cathodes that can fully couple with the well-developed battery-type anodes severely restricts the further development of SICs. Here, we develop a compact yet highly ordered graphene solid (HOGS), which combines the merits of high density and high porosity and, more attractively, possesses a highly ordered lamellar texture with low pore tortuosity. As the capacitive cathode of SICs, HOGS delivers a record-high volumetric capacity (303 F cm or 219 mA h cm at 0.05 A g), a superior rate capability (185 F cm or 139 mA h cm even at 10 A g), and an outstanding cycling stability (over 80% after 10 000 cycles). The material design and construction strategies reported here can be easily extended to other metal-ion-based energy storage technologies, exhibiting universal potentials in compact electrochemical energy storage systems.
作为一种新兴的电化学储能装置，钠离子电容器（SIC）具有实现高能量密度、高功率密度以及低成本、长寿命的潜力。遗憾的是，缺乏能够与成熟的电池型负极充分匹配的高性能电容型正极，这严重限制了SIC的进一步发展。在此，我们开发了一种紧凑但高度有序的石墨烯固体（HOGS），它兼具高密度和高孔隙率的优点，更吸引人的是，具有高度有序的层状结构且孔隙曲折度低。作为SIC的电容型正极，HOGS展现出创纪录的高体积容量（在0.05 A g时为303 F cm³或219 mA h cm³）、优异的倍率性能（即使在10 A g时仍为185 F cm³或139 mA h cm³）以及出色的循环稳定性（10000次循环后超过80%）。本文报道的材料设计和构建策略可轻松扩展到其他基于金属离子的储能技术，在紧凑的电化学储能系统中展现出广泛的应用潜力。
