Novel Ni6MnO8/NiMnO3 composite as a highly stable electrode material for supercapacitors

In our work, a Ni6MnO8/NiMnO3 composite, which are porous cuboids coated with porous spheres to form a 3D hierarchical structure, is successfully fabricated using a one-step solvothermal method. As an electrode material, this composite possesses high specific capacitance (291.9F/g at 1 A/g) and excellent rate capability (77.2% of specific capacitance maintained at 10 A/g). The specific capacitance retention is 83.4% after 5000 charge/discharge cycles at a current density of 3 A/g. The enhanced performance is mainly attributed to the synergistic effect of Ni6MnO8 and NiMnO3, which can provide more active sites for redox reaction and contribute to electrolyte ion transport. Results demostrate that the Ni6MnO8/NiMnO3 composite as an electrode material in supercapacitors exhibits outstanding electrochemical performance and potential for various applications. (C) 2019 Elsevier B.V. All rights reserved.