Facile Synthesis of MgCo_2O_4@MMoO_4 (M = Co, Ni) Nanosheet Arrays on Nickel Foam as an Advanced Electrode for Asymmetric Supercapacitors

摘要

Through a simple two-step solvothermal method, MgCo_(2)O_(4)@MMoO_(4) (M = Co, Ni) nanosheet arrays were grown on nickel foam. In a 1 M KOH aqueous solution, the two battery-type electrode materials showed high specific capacities up to 1089.94 and 1111.57 C g~(–1) at a current density of 1 mA cm~(–2). When these battery-type electrode materials are applied to ASC devices, they exhibit high specific capacity, stable cycle life, and high energy density. The excellent electrochemical performance of the MgCo_(2)O_(4)@MMoO_(4) electrode material is due to the reasonable combination of MgCo_(2)O_(4) and MMoO_(4), so that the electrochemically active site of the electrolyte–electrode interface is greatly increased. At the same time, the morphology and thickness of the MMoO_(4) layer also affect the penetration of the electrolyte solution and the electron/ion transport process. Practical application of these materials in the field of electrochemical energy storage has great prospect.