▎ 摘　　要

NOVELTY - Preparing laser-assisted synthesis of cobalt ferrite composite nitrogen-doped three-dimensional porous graphene involves using graphene oxide as a raw material, preparing a graphene oxide ethanol solution, ultrasonically crushing and mixing well. The mixed solution is taken into a volumetric flask, and irradiated with a nanosecond parallel pulse laser for 10-30 minutes under continuous stirring in an ice-water bath. The obtained sample is subjected to high-speed centrifugation at a rotation speed of 10,000-18000 rpm, and the precipitate is collected and lyophilized to obtain a two-dimensional graphene sheet having a mesoporous structure. The graphene is weighed, put it in deionized water to make the concentration 0.5-2 mg/mL, and then added urea with a mass ratio of 3:1 to the graphene, and mixed it by ultrasonic. USE - Method for preparing laser-assisted synthesis of cobalt ferrite composite nitrogen-doped three-dimensional porous graphene. ADVANTAGE - The method enables to prepare laser-assisted synthesis of cobalt ferrite composite nitrogen-doped three-dimensional porous graphene, that is simple in operation and easy to control, and under the assistance of laser, it aims at preparing a three-dimensional composite material with a large specific surface area and cross-linked pores by adjusting the graphene concentration of the reaction liquid. DETAILED DESCRIPTION - Preparing laser-assisted synthesis of cobalt ferrite composite nitrogen-doped three-dimensional porous graphene involves using graphene oxide as a raw material, preparing a graphene oxide ethanol solution, ultrasonically crushing and mixing well. The mixed solution is taken into a volumetric flask, and irradiated with a nanosecond parallel pulse laser for 10-30 minutes under continuous stirring in an ice-water bath. The obtained sample is subjected to high-speed centrifugation at a rotation speed of 10,000-18000 rpm, and the precipitate is collected and lyophilized to obtain a two-dimensional graphene sheet having a mesoporous structure. The graphene is weighed, put it in deionized water to make the concentration 0.5-2 mg/mL, and then added urea with a mass ratio of 3:1 to the graphene, and mixed it by ultrasonic. The ammonia water is added in the same proportion as urea, transferred the mixed solution to a polytetrafluoroethylene liner and placed in a high temperature oven for hydrothermal reaction for hours. After that, the inner liner of the reactor after the reaction is taken out, and after cooling, iron chloride tetrahydrate (FeCl2.4H2O) and cobal chloride hexahydrate (CoCl2.6H2O) with an iron, and cobalt mass ratio of 2:1 are added, and then placed in an oven for hydrothermal reaction. After the reaction is completed, the obtained sample is subjected to high-speed centrifugation at a rotation speed of 10,000-18000 revolutions/minute, washed various times with pure water, and the precipitate is lyophilized and collected, and obtained laser-assisted synthesis of cobalt ferrite composite nitrogen-doped three-dimensional porous graphene.