Self-Supported Co 3 O 4 @Mo-Co 3 O 4 Needle-like Nanosheet Heterostructured Architectures of Battery-Type Electrodes for High-Performance Asymmetric Supercapacitors.

Herein, this report uses Co 3 O 4 nanoneedles to decorate Mo-Co 3 O 4 nanosheets over Ni foam, which were fabricated by the hydrothermal route, in order to create a supercapacitor material which is compared with its counterparts. The surface morphology of the developed material was investigated through scanning electron microscopy and the structural properties were evaluated using XRD. The charging storage activities of the electrode materials were evaluated mainly by cyclic voltammetry and galvanostatic charge-discharge investigations. In comparison to binary metal oxides, the specific capacities for the composite Co 3 O 4 @Mo-Co 3 O 4 nanosheets and Co 3 O 4 nano-needles were calculated to be 814, and 615 C g -1 at a current density of 1 A g -1 , respectively. The electrode of the composite Co 3 O 4 @Mo-Co 3 O 4 nanosheets displayed superior stability during 4000 cycles, with a capacity of around 90%. The asymmetric Co 3 O 4 @Mo-Co 3 O 4 //AC device achieved a maximum specific energy of 51.35 Wh Kg -1 and power density of 790 W kg -1 . The Co 3 O 4 @Mo-Co 3 O 4 //AC device capacity decreased by only 12.1% after 4000 long GCD cycles, which is considerably higher than that of similar electrodes. All these results reveal that the Co 3 O 4 @Mo-Co 3 O 4 nanocomposite is a very promising electrode material and a stabled supercapacitor.