Hydrothermal Synthesis of Polyoxovanadate-based MOFs Microsphere as Supercapacitor

Polyoxovanadate-based MOFs microsphere electrode material, [Ni_2(4,4?-bipyridine)_3(H_2O)_2V_4O_(12)]·2.5 H_2O, was synthesized through a simple hydrothermal method, and then characterized through FT-IR, XRD and SEM. Electrochemical properties of the sample as supercapacitor electrodes in aqueous electrolyte were developed and studied by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy techniques. Results showed that a high specific capacitance of 152.36 F g^(-1) at current density of 1 A g^(-1) in 2 M KOH electrolyte, and 97.62% retention after 2500 charge-discharge cycles at current density of 4 A g^(-1), which is promising for applications in supercapacitors.