Corresponding Author

WANG Wei(clwang@ouc.edu.cn);
LANG Jun-wei(jwlang@licp.cas.cn)


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 RuO2 (nanoshpheres,1.69 g·cm-3) and Co-Ni oxide (nanoflakes, 2.14 g·cm-3), the RuO2//KOH//Co-Ni oxide 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·cm-3) 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 of 1.4 V at a current density of 2 A·g-1 in life cycle test, indicating high electrochemical stability.

Graphical Abstract


metal oxide, Co-Ni oxide nanoflakes, RuO2 nanoshpheres, high gravimetric and volumetric energy density, aqueous asymmetric supercapacitors

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