3D flower-like NiCo2O4 electrode material prepared by a modified solvothermal method for supercapacitor

•3D flower-like NiCo2O4 electrode material has been fabricated via a modified solvothermal method combined with calcination.•Rarely used guanidine hydrochloride was applied to produce hydroxyl anions.•The as-prepared NiCo2O4 sample possesses hierarchical mesopores and large specific surface area.•The composite displays a high specific capacitance, i.e. 1609 F g−1 at current density of 1 A g−1.

Novel 3D hierarchical mesoporous flower-like NiCo2O4 electrode material was prepared by water-ethanol mixed solvothermal method combining the calcination process. Nickel sulfate hexahydrate (NiSO4·6H2O), cobalt sulfate heptahydrate (CoSO4·7H2O), rare-used guanidine (CH6ClN3) were used as nickel and cobalt sources, precipitant of weak base, respectively. The resultant samples were characterized by X-ray diffraction, scanning electron microscopy, N2 adsorption and desorption and transmission electron microscopy. The prepared NiCo2O4 material exhibited excellent electrochemical performance-with a high specific capacitance of 1609 F g−1 at 1 A g−1, and high capacity retention of 85% after a 1000-cycle charge-discharge at 10 A g−1.