Effect of sonication time on the properties of multilayer graphene

Abstract

Graphene, an extraordinary two-dimensional carbon nanostructure, has attracted global attention due to its electronic, mechanical and chemical properties. This work reports a sonochemical method to synthesize multilayer graphene with different sonication times of 15, 30 and 45 min. Characterization results of Atomic Force Microscopy (AFM), Field Emission Scanning Electron Microscopy (FESEM) and Raman spectroscopy show that multilayer graphene (MLG) with sonication time of 45 min is the optimum time to exfoliate high-quality graphene from graphite flakes. From the AFM results, MLG with sonication time of 45 min has thinner graphene sheet which is 0.49 nm compared to sonication time of 15 min and 30 min. FESEM also shows MLG with sonication time of 45 min has thinner graphene sheet approximately 26.84 nm compared to sonication time of 15 min and 30 min. Characterization results of Raman spectrum show that MLG with sonication time of 45 min has highest I2D/IG ratio of 0.54 among the others. Therefore, 45 min is considered as the maximum sonication time without affect the quality of graphene.