Exceptional pseudocapacitive properties of hierarchical NiO ultrafine nanowires grown on mesoporous NiO nanosheets

Hierarchical NiO ultrafine nanowires grown on mesoporous NiO nanosheets with Ni foam as a substrate synthesized by a facile and effective hydrothermal method showed exceptionally high specific capacitance (1349 F g(-1) at a current density of 5 A g(-1)), good rate performance (similar to 58% retention of the initial capacitance from 3 A g(-1) to 50 A g(-1)) and superior electrochemical cycling stability (similar to 87% retention after 2000 cycles). The remarkable electrochemical performance can make the unique hierarchical NiO nanosheets/nanowires to be a perspective electrode material for electrochemical energy storage applications.