▎ 摘　　要

NOVELTY - Photo-thermal effect multi-level structure microspheric graphene aerogel comprises metal nano particles as catalyst, and multi-layered micro-spherical graphene aerogels with carbon nanotubes grown on the oriented graphene micropores. USE - The photothermal effect multi-level structure microspheric graphene aerogel is used as a photothermal conversion material (claimed). ADVANTAGE - The graphene aerogel: can rapidly rise from room temperature to 83 degrees C within 1 minute under 1000 W/m2 light i.e. higher than pure graphene samples at 73 degrees C, and can be used for viscosity reduction adsorption, seawater desalination, catalytic reaction, biomedical and other fields. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the graphene aerogel, comprising (i) preparing graphite oxide dispersion liquid: (ii) dispersing the chitosan powder in an aqueous solution of 1-5 wt.% acetic acid, and stirring to obtain a chitosan solution, and stirring and mixing the chitosan solution and the graphene oxide dispersion, adding a small amount of concentrated ammonia to deprotonate and performing ultrasonic to obtain chitosan/graphene oxide composition dispersion, adding the metal salt catalyst precursor to the chitosan/graphene oxide composition dispersion, and stirring to obtain chitosan/graphene oxide composition dispersion containing catalyst; (iii) injecting the chitosan/graphene oxide composition dispersion liquid containing the catalyst into the n-hexane coagulation bath of -60 to -90 degrees C using a micro syringe pump to obtain droplets afterwards, separating the ice microspheres from n-hexane by vacuum suction filtration, and then freeze-drying at -75 degrees C to -80 degrees C in vacuum to obtain chitosan/graphene oxide microsphere aerogel; (iv) taking the carbon nanotube-reduced oxidation graphene microsphere aerogel prepared by vapor deposition, placing the chitosan/graphene oxide microsphere aerogel obtained in step (iii) in the corundum boat, placing into a single temperature zone tube furnace for carbon nanotube growth and high temperature reduction process, the entire heating procedure is: (a) using a heating rate of 1-10 degrees C/minute in a mixed atmosphere of hydrogen and argon from room temperature to 450-550 degrees C, reducing metal ions into nanoparticles, and insulating for 12 hours, (b) under the mixed atmosphere of hydrogen and argon in step (a) at a temperature increase rate of 1-10 degrees C/minute, after heating and simultaneously introducing acetylene gas as a carbon source, and introducing acetylene gas for a period of time, then turning off the acetylene gas and continuing to heat in the mixed atmosphere of hydrogen and argon for 30 minutes, and (c) maintaining the heating rate of 110 degrees C/minute in the mixed atmosphere of hydrogen and argon, increase the temperature to 850-950 degrees C high temperature reduction oxidation graphene, and maintaining for 1-2 hours, and then naturally reducing the temperature.