▎ 摘　　要

NOVELTY - Preparation method of graphene, involves (a) taking graphite, crushing and grinding to obtain graphite powder, pouring the graphite powder and deionized water into the interior of the stirring device for pre-stirring, adding nitric acid solution, stirring, and adding potassium dichromate solution for oxidation reaction to prepare a graphite oxide suspension, (b) filtering to obtain graphite oxide solid matter, and drying the graphite oxide solids to obtain pure graphite oxide powder, (c) pouring the graphite oxide powder in step (b) into pure water to make a solvent, and ultrasonically dispersing the graphite oxide powder solvent to obtain a graphene oxide solvent, (d) putting sodium borohydride solution into the solvent of step (c), stirring, and reacting to prepare a graphene suspension, and (e) adding conductive additives to the graphene suspension in step (d), stirring, filtering and drying the solid to obtain the finished graphene powder. USE - Preparation method of graphene. ADVANTAGE - The method increases the conductivity of graphene in the process of preparing graphene, and makes up for the loss of electrical properties of the graphene material during the preparation process of the redox method, and simultaneously expands the application range of graphene materials. The method solves the problem of the current process of preparing graphene by redox method such as the reaction causes defects in the structure of the graphene, which leads to a decrease in the conductivity of the graphene material, and causes the problem that the application of the graphene material is restricted. DETAILED DESCRIPTION - Preparation method of graphene, involves (a) taking graphite, crushing and grinding to obtain graphite powder, pouring the graphite powder and deionized water into the interior of the stirring device for pre-stirring, simultaneously adding 50-60% nitric acid solution to the inside of the stirring device and stirring for 20-30 minutes, adding 35-75% potassium dichromate solution for oxidation reaction for 50-60 minutes, and after reacting, preparing a graphite oxide suspension, (b) filtering the graphite oxide suspension obtained in step (a), filtering to obtain graphite oxide solid matter, simultaneously using deionized water to rinse the graphite oxide solids, and drying the graphite oxide solids at 50-100 degrees C to obtain pure graphite oxide powder, (c) pouring the graphite oxide powder in step (b) into pure water to make a solvent, placing the graphite oxide powder solvent inside the ultrasonic dispersion device, and ultrasonically dispersing the graphite oxide powder solvent to obtain a graphene oxide solvent, (d) putting 45-60% sodium borohydride solution into the solvent of step (c), stirring, and reacting at 30-60 degrees C for 0.5-1.5 hours, to prepare a graphene suspension, and (e) adding conductive additives to the graphene suspension in step (d), stirring for 1-2 hours, taking out the solids in the stirring vessel, filtering and drying the solids to obtain the finished graphene powder. An INDEPENDENT CLAIM is included for a graphene preparation device, including a stirring reactor and an ultrasonic dispersion stirrer, where one side of the stirring reactor is connected with a filter tank, and the other side of the filter tank is connected with a cleaning tank, and a dryer is connected to the other side of the cleaning tank.