材料期刊网

为了研究并消除石墨团聚对石墨烯产量的影响，在连续性稳定分散状态和非连续性稳定分散状态下采用机械剥离法制备了石墨烯溶液，通过zeta电位表征了制备过程中石墨的团聚情况，利用吸光度测试研究了石墨溶液的分散状态，并通过原子力显微镜表征了制备出的石墨烯结构.结果表明，石墨片层结构被剥离使石墨表面积被释放，导致石墨的团聚势能增加，剥离效果和石墨烯产率下降；连续性稳定分散状态克服了随剥离过程剧增的团聚势能，经4 h机械剥离制备，上层清液石墨烯产量提高率达到21．9％；制备出的厚度为1~2 nm 的单层石墨烯结构完好且处于良好分散状态；该方法为大规模制备石墨烯提供理论和工程指导.

In order to analyze and eliminate the effect of aggregation of graphite to the yield of graphene,the gra-phene dispersion were prepared under the continues stable disperse state and non-continues stable disperse state. The aggregation of graphite during the preparation process was characterized by zeta potential.The disperse state of graphite dispersion was studied by measuring its absorbance.And the prepared graphene structures were characterized by atomic force microscope.Results show that the surface area of graphite is increased by ex-foliating the graphite sheets,leading to the increasing of potential energy of aggregation of graphite and the de-crease of the efficiency of exfoliation and graphene yield.The increasing potential energy of aggregation was o-vercame by continues stable dispersing,and the yield growth rate of graphene in top graphene dispersion reached at 2 1 .9% by mechanical exfoliating graphite sheets for 4 h.The monolayer graphene with thickness of 1-2 nm was prepared,which show well structural integrity and free of aggregation.The method of continues stable dispersing gives a theoretical and practical guide for high-yield preparation of graphene.