Fabrication Of Nickel Foam Substrate Composite Electrodes And Research Of Electrochemical Performances

Supercapacitors（SCs）with high-effciency energy storage devices have attracted considerable attention because of their excellent rate capability,long cycle life,and ultrahigh power density.The micro/nano structure in transition metal compound on nickel foam was farbrcated with different methods,which provide the deep analysis of the close relationship between reaction condition and structure from microcosmic level and the deep analysis of the close relationship between structure and electrochemical performance from microcosmic level.The details are summarized as follows:1.Porous Mn₂O₃ microsheet arrays with the average size of about 16 nm on nickel foam as composite electrode of SCs have been fabricated by chemical reaction at room temperature.This electrode exhibits a specific capacitance of 566.6 F g^-1 at0.5 A g^-1 and retains 51.9%when the current density is increased to 20 A g^-1.2.Porous MnCo₂O₄ nanorod arrays with the average diameter of⁶.7 nm on nickel foam as electrode materials have been fabricated through a co-precipitating reaction at room temperature.This electrode exhibits the good capacitance of 845.6F g^-1 at 1 A g^-1.After 2000 cycles,it shows the retention of 90.2%of the first test.The MnCo₂O₄//rGO asymmetric supercapacitor with the stable opening voltage of1.6 V delivers an energy density of 53.7 Wh kg^-1 and a power density of 8000 W kg-¹.3.The MnMoO₄?H₂O@MnO₂ core-shell nanosheet arrays on nickel foam as composite electrode of SCs have been fabricated by a two-step hydrothermal method.The core-shell structure significantly increases the number of active sites for Faradaic reactions,shortens the ions diffusion pathway and facilitates the electrolytes penetration.This electrode reaches to a high specific capacitance of3560 F g^-1 at 1 A g^-1.MnMoO₄?H₂O@MnO₂//AC asymmetric supercapacitor exhibits an energy density of 45.6 Wh kg^?1 and a power density of 507.3 W kg^?1.4.The Ni₃S₂ nanosheet nanosheet arrays on nickel foam as composite electrode of SCs have been fabricated by one-step electrodeposition.This electrode displays773.6 F g^-1 at 1 A g^-1 and the excellent rate property(84.3%at 10 A g^-1).The Ni₃S₂//rGO device exhibits a high power density of 1.6 kW kg^-1 and an energy density of 41.2 Wh kg^-1.