▎ 摘　　要

NOVELTY - Preparation of graphene foam involves placing foam metal in chemical vapor deposition atmospheric furnace, continuously filling inert gas into furnace, introducing hydrogen gas, heating at 850-1080 degrees C, introducing carbon source gas into the furnace while maintaining the temperature of the furnace at 850-1080 degrees C, performing chemical vapor deposition, cooling the metal foam to room temperature, immersing the resultant foam metal in an etching solution, then placing the resultant foam metal in pure water, leaving still for 0.1-12 hours, washing with pure water to neutral, and drying. USE - Preparation of graphene foam used in high-sensitive sensor, energy storage and flexible electronic device, and adsorption and electrocatalysis applications. ADVANTAGE - The method enables efficient, economical, simple, convenient and large-scale preparation of flexible graphene foam having controllable product appearance, small specific gravity, large specific surface area, high strength, and excellent flexibility and electroconductivity and thermal conductivity. The carbon nano toughening agent is covalently bonded with the graphene to achieve in-situ toughening of the graphene foam, such that mechanical property of the graphene foam is improved. DETAILED DESCRIPTION - Preparation of graphene foam involves completely immersing foam metal in 0.01-2 M dilute hydrochloric acid, ultrasonically cleaning at 60-100 W for 3-20 minutes to remove surface oxide, washing the foam metal with deionized water for 3-20 minutes to neutral until residual hydrochloric acid is completely removed, and anhydrous ethanol for 3-20 minutes, drying, evenly coating the carbon nano toughening agent solution on the metal foam, drying, placing the foam metal in a chemical vapor deposition atmospheric furnace, vacuumizing the furnace to -0.10-0.15 MPa, continuously filling inert gas into the furnace, introducing hydrogen gas, heating at 850-1080 degrees C, reducing the temperature for 10-60 minutes, introducing carbon source gas into the furnace while maintaining the temperature of the furnace at 850-1080 degrees C, performing chemical vapor deposition process, terminating flow of carbon source gas and hydrogen gas, introducing inert gas into the furnace, rapidly cooling the metal foam to room temperature at 10-200 degrees C/minute, obtaining foam metal having carbon nano toughening agent on its surface, immersing the foam metal in an etching solution, etching, placing the resultant foam metal in pure water, leaving still for 0.1-12 hours, washing several times with pure water to neutral until hydrochloric acid and ferric chloride residues are completely removed, and drying. The etching solution comprises ferric chloride, hydrochloric acid and deionized water in volume ratio of 1 mol:0.1-5 mol:0.1-10 L. The carbon nano toughening agent solution is obtained by dispersing carbon nano toughening agent in 0.1-5 g/L surfactant aqueous solution, and ultrasonically processing at 60-90 W for 10-30 minutes to obtain 0.1-5 g/L carbon nano toughening agent solution. The loading amount of carbon nano toughening agent on the metal foam is 0.1-5 mg/cm2. The flow ratio of hydrogen gas and carbon source gas is 1:1-1:20.