surface oxidation of graphite and subsequent sonication exfoliation to prepare graphene without high cost reduction process and method of fabricating the same

摘要

The present invention relates to a method for producing graphene by modifying the Hummers method to induce surface oxidation of graphite and peeling it by ultrasonic waves without a reducing process using a toxic substance. For the surface oxidation, the oxidation temperature was fixed at 20 ° C and the time was changed to 15, 30, and 45 minutes. Ultrasonic separation was performed using a commercial ultrasonic cleaner at 40 kHz. Separation of graphene was performed by using natural sedimentation method instead of general centrifugation. The separation time was optimized by TEM analysis according to sedimentation time, and the sheet resistance of the separated graphene was measured to estimate the quality. As a result of TEM analysis, several layer graphenes were considered to be produced rather than single layer graphene. Their sheet resistance was as high as ~ 12,000 Ω / □, but the yield was as low as ~ 20%.