Preparation and performance of NiCo_2O_4 nanowires-loaded graphene as supercapacitor material

摘要

NiCo_2O_4 nanowires-loaded reduced graphene oxide composite (NiCo_2O_4@RGO) was prepared by a facile hydrothermal method without any surfactant. Hexamethylenetetramine was introduced as a structure directing and assembling agent to the synthesis of NiCo_2O_4 nanowires. NiCo_2O_4 nanowires with an average size of 80 x 10 nm~2 are uniformly and densely dispersed on the graphene sheets. Cyclic voltammetry and galvanostatic charge-discharge measurements on NiCo_2O_4@RGO indicated a high specific capacitance of 737 F g~(-1) at a current density of 1 A g~(-1) and only 6% loss of the initial specific capacitance after 3000 charge/discharge cycles at 4 A g~(-1) in 2 M KOH electrolyte, which is valuable for practical application in supercapacitors.