Pulse Electrodeposition of α-Nickel Hydroxide with Flower-Like Nanostructure for Supercapacitors

Abstract

Nickel hydroxide electrodes with flower-like structure were prepared by pulse electrodeposition method. The samples were characterized by XRD, SEM and electrochemical measurements. XRD results show a typical characteristics of α-Ni(OH)2. SEM results show the morphology can be controlled by the ratio between on-time (Ton) and off-time (Toff). If Tonis constant to 10s, a flower-like structure will be obtained when Toffis bigger than 20s. Electrochemical tests revealed that the Nickel hydroxide electrodes prepared atTon=10 s and Toff= 30s not only has higher discharge capacity but also exhibits superior stability of capacity during charge-discharge cycling. The maximum specific capacitance in the first cycle is 737.74 F/g and their specific capacitance become stable after cycling 20 times.