Hydrothermal preparation of porous NiO nanoflake arrays@V2O5 nanoparticles composite for high performance supercapacitive electrode material

In this paper, porous NiO nanoflake arrays@V2O5 nanoparticles (PNFAs@VNPs) composite is fabricated on Ni foam through a facile hydrothermal process. The PNFAs@VNPs composite has an ordered array structure, a large active surface, and favorable physical stability. Based on the CV profile, the specific capacitance can achieve 950 F g-1 and remain stable at 95.8 % of the original value after 5000 loops. When the PNFAs@VNPs composite is assembled into a symmetric supercapacitor, the energy density can reach 67.0 W h kg- 1 at a power density of 550 W kg 1. Even if the power density rises to 11,000 W kg 1, the energy density can still be held at 25.3 W h kg-1. The high supercapacitive property of the PNFAs@VNPs composite is owed to the synergic action of the PNFAs and VNPs. The PNFAs@VNPs composite with the advantages of battery-type and capacitive-type pseudocapacitances has higher charge transfer dynamics, making it a potential supercapacitive electrode material.