Preparing composites of Ni-Al layered double hydroxide/graphene electrode for supercapacitors and their electrochemical properties

The composites of Ni-Al layered double hydroxide (Ni-Al LDH)/graphene (GR) had been synthesized through the hydrothermal route in this work. The mechanism of the composites depended on XRD. Meanwhile, SEM was used to record the morphological structure of the composites. The electrochemical properties were analyzed through the charge-discharge of constant current, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The composites of Ni-Al LDH/GR possessed a layered structure and the structure was uniformly dispersed on the graphene. The given discharge capacity of the composites of Ni-Al LDH/GR was higher than the value of bare Ni-Al LDH, which was approximately 400 F . g(-1) in the speed of 1 A g(-1); Meanwhile, the capacitance retention was still more than 1 time higher compared with the value of Ni-Al LDH for 500 cycles at 1 A g(-1).