Abstract: Graphene is prepared through liquid phase exfoliation in a binary solvent system composing of N-methyl pyrrolidone (NMP) and n-butyl alcohol (NBA) to explore the conditions of preparing high quality and high concentration graphene.Through comparing the exfoliation effects of graphite within different volumetric ratio of solvents,the optimal ratio is confirmed as V(NMP):V(NBA)=1.5:1.It is found via orthogonal experiments that the initial mass concentration of graphite has the greatest influence on the concentration of graphene after exfoliation,followed by the ultrasonic power,time and temperature.The result shows that 80% of prepared graphene are of less layer,with structural integrity and 3-4 microns in lamella size,and the mass concentration of graphene solution can reach 7.2 mg·mL-1 when the initial mass concentration of graphite is 10 mg·mL-1.The yield and lamella size of graphene prepared in this system has a significant improvement than that reported in previous literatures.
赵木, 黄国强. N-甲基吡咯烷酮与正丁醇液相剥离制备高浓度石墨烯[J]. 现代化工, 2018, 38(11): 97-101.
ZHAO Mu, HUANG Guo-qiang. Preparation of high concentration graphene by liquid phase exfoliation in NMP and butyl alcohol. Modern Chemical Industry, 2018, 38(11): 97-101.
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