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论文类型：期刊论文

发表时间：2017-08-01

发表刊物：RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A

收录刊物：SCIE、EI、Scopus

卷号：91

期号：8

页面范围：1517-1526

ISSN号：0036-0244

关键字：graphene nanoplatelets; sonication time; dispersion; absorbance; methylcellulose

摘要：The homogenous graphene nanoplatelets (GNP) suspension had been prepared through ultrasonic exfoliation in the presence of methylcellulose (MC) as dispersant. The influence of different sonication times on dispersing of aqueous GNP suspension was monitored by UV-Vis absorbance, sedimentation test, optical microscope and transmission electron microscope (TEM). The study of UV-Vis absorbance verifies that the minimum sonication time to break the 0.1 g/L concentration of bundled GNPs is 20 min; furthermore, the GNP suspension achieved the best dispersion, when sonication time increased up to 80 min. From optical microscope images of GNPs, the agglomeration of GNPs was broken by enough sonication energy, and the distribution of GNPs particles became more uniform. The dispersing mechanism had been discussed and simulated by HRTEM image. The bundled GNPs were exfoliated by cavitation effect of ultrasonic irradiation, meanwhile, the dispersant adsorbed on the surface of GNPs prevented re-entanglement by forming steric hindrance.