Surface modification method of waste nickel-based electrode, catalytic electrode and electrochemical battery

The embodiment of the invention discloses a surface modification method of a waste nickel-based electrode, a catalytic electrode and an electrochemical battery. The surface modification method comprises the following steps: taking a waste nickel-based electrode as a target substrate; immersing the target substrate into an acid solution for etching treatment, and forming a nickel hydroxide nanosheet array on the surface of the target substrate; immersing the etched target substrate into a metal salt solution, and performing electrochemical conversion treatment on the nickel hydroxide nanosheet array to obtain a nickel-based composite nanosheet array containing metal cations in the metal salt solution; and immersing the target substrate subjected to electrochemical conversion treatment into an alkaline solution, and performing electrochemical activation treatment on the nickel-based composite nanosheet array to obtain a modified nickel-based electrode with a nickel-based active nanosheet array formed on the sur