The effects of carbon coating on the electrochemical performance of Zn-Al layer double oxides in nickel-zinc secondary cells

Carbon-coated Zn-Al layer double oxide (Zn-Al-LDOs) is synthesized by hydrothermal-calcined method and investigated as an anode material for the Ni-Zn cells. The as-obtained products are characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrum (EDS), and X-ray diffraction (XRD), which prove that carbon-coated Zn-Al-LDOs are well-crystallized and carbon formed on the surface of Zn-Al-LDOs is amorphous. The electrochemical performances of the carbon-coated Zn-Al-LDOs electrode with different carbon content and pure Zn-Al-LDOs electrode are investigated by the cyclic voltammograms (CV), AC electrochemical impedance spectroscopy (EIS), Tafel plot (TAFEL), and galvanostatic charge-discharge (GCD) measurements. Compared with the pure Zn-Al-LDOs electrode, the carbon-coated Zn-Al-LDOs electrode shows better reversibility, higher specific capacity, and more excellent cycling performance.