A cobalt-aluminium layered double hydroxide with a nickel core-shell structure nanocomposite for supercapacitor...

Layered double hydroxides (LDHs) are promising structures in applications including supercapacitors, which are claimed to help in arresting environmental chaos by their ability in energy storing. In this work, a Co-Al LDH and its metallic Ni core-shell nanocomposite were prepared and described using Fourier transform infrared (FTIR), X-ray diffractometer (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. The two materials were electrochemically examined. The specific capacitance in current density of 1 A g^-1 was 90 C g^-1 (341.75 F g^-1) and 210 C g^-1 (792.5 F g^-1) for the LDH and its composite, respectively. Compared with similar composites, the specific capacitance, especially the composite has a larger value in the order of 1.08-5.82 of magnitude. Moreover, the cycle stability test shows a slow drop at current density 4 A g^-1 within 3,000 cycles, meaning that for the pure hydroxide and its Ni composite, a loss of 21% and 10% of specific capacitance was observed, respectively.