Copper Integrated Electrode with Convertible Oxidation State and Preparation Method and Application Method thereof

A preparation method of a copper integrated electrode with a convertible oxidation state, comprising the following steps:

• 1) cutting a copper foam into a copper foam strip, and washing the copper foam strip with ethanol and acetone to remove surface impurities of the copper foam strip to obtain a washed copper foam strip;
• 2) drying the washed copper foam strip obtained in step 1) at room temperature to obtain a dried copper foam strip, and immersing the dried copper foam strip in a graphene oxide solution with a concentration of 0.1 mg/mL-10 mg/mL for 1 min-10 min, covering a surface of the dried copper foam strip with a carbon layer to obtain a carbon coated copper foam strip, transferring the carbon coated copper foam strip to a constant temperature oven, and drying the carbon coated copper foam strip for 1 h-10 h at 50° C.-100° C. to obtain a copper foam carrier;
• 3) calcining the copper foam carrier obtained in step 2) for 1 h-5 h at 200° C.-500° C. in a tubular furnace with an argon atmosphere to obtain a C—Cu electrode substrate;
• 4) after cutting the C—Cu electrode substrate obtained in step 3) to a size of 1 cm×1 cm to obtain a trimmed C—Cu electrode substrate, cleaning the trimmed C—Cu electrode substrate 2-3 times with ultrapure water to obtain a first washed C—Cu electrode substrate, placing the first washed C—Cu electrode substrate in an alkali solution with a concentration of 0.1 M-1 M for a CV scanning for 1-400 cycles in a voltage range of −1 V-+1 V by a cyclic voltammetry to obtain a treated C—Cu electrode substrate, then cleaning the treated C—Cu electrode substrate 2-3 times with ultrapure water again to obtain a second washed C—Cu electrode substrate and drying the second washed C—Cu electrode substrate to obtain the copper integrated electrode with the convertible oxidation state.