▎ 摘　　要

NOVELTY - Preparation of graphene, involves (1) cleaning the substrate, placing the pre-cleaned substrate in acetone, ultrasonically cleaning with ethanol for 20-40 minutes, then wiping with lint-free cloth, (2) loading the sample to transfer the cleaned substrate to the vacuum chamber, placing on the lower base plate, connecting base plate to pulsed negative bias power source, (3) vacuuming and cleaning again using mechanical pump, sequentially evacuating the chamber using root pump and molecular pump, until the vacuum in the cavity is less than 1.0x 10-3 Pa, switching off the molecular pump, introducing argon gas, plasma cleaning, removing surface burrs and contaminants, (4) carrying out plasma low temperature nitriding process, bombarding the substrate, (5) passing methane at pulse bias of (-800)-(-300) V and deposition pressure of 5-30 Pa for 0.5-3 hours under the condition of duty ratio of 50-70%. USE - Method for preparing graphene. ADVANTAGE - The method enables preparation of reproducible graphene with simple equipment, high yield and low production cost, is operated and controlled easily, and reduces friction coefficient between substrate and polished stainless steel, and effectively avoids the low bonding strength between graphene and substrate. DETAILED DESCRIPTION - The vacuum chamber has diameter and height of 200~500 mm. The diameter of the upper plate and the diameter of the lower plate are 100-600 mm. The distance between the plates is 30-110 mm. The step (3) involves introducing argon gas into chamber at pulse bias of (-800)-(-600) V, plasma cleaning for 20-50 minutes with a duty cycle of 50-70%. The step (4) involves carrying out plasma low temperature nitriding process at pulse bias of (-900)-(-400) V and deposition pressure of 10-30 Pa, bombarding the substrate for 1-3 hours under the condition of 50-70% duty cycle.