兼具高质量和高体积能量密度的水系全金属氧化物不对称超级电容器（英文）

An Aqueous All-Metal Oxide Asymmetric Supercapacitor with High Gravimetric and Volumetric Energy Densities

超级电容器只有兼具高质量和高体积能量密度才能拥有更广泛的应用价值.本文采用具有纳米结构及高填充密度的RuO_2(纳米球,1.69 g·cm-3)和Co-Ni氧化物(纳米片,2.14 g·cm-3)分别作为负极和正极材料,成功地构筑了氧化物非对称超级电容器.所得不对称超级电容器具有高电压窗口、高质量比容量(217.5 F·g-1)和高体积比容量(412.3 F·cm-3)、高质量能量密度(61.8 Wh·kg-1)和高体积能量密度(121Wh·L-1)的优良性能,在1.4 V的电压下以2 A·g-1的电流密度历经5000次循环后比容量保持率为87%.

Only with both high gravimetric and high volumetric energy densities,can supercapacitors find more extensive applications.In this paper,by making good use of the interesting nanostructures and the high packing densities of Ru1.69 g·cm3）and Co-Ni oxide（nanoflakes,2.14 g·cm3）,the Ruoxide all-metal oxide asymmetric supercapacitors with high performance were successfully fabricated,which led to the maximum specific capacitance of 217.5 F·g-1（412.3 F·cm3）and specific energy density of 61.8 Wh·kg-1（121 Wh·L-1）in a cell voltage between 0 and 1.5 V in KOH electrolyte.In addition,the constructed supercapacitor device could retain 87%of the initial specific capacitance even at 5000th cycle with the cell voltage of1.4 V at a current density of 2 A·g-1 in life cycle test,indicating high electrochemical stability.