化学剥离膨胀石墨制备石墨烯及属性研究

Preparation of Graphene from Expanded Graphite by Chemical Stripping and Properties

以膨胀石墨为原料,采用化学一步法剥离膨胀石墨制备石墨烯,对产物的产率、电导率、缺陷等进行表征分析。结果表明,在膨胀石墨与浓硫酸质量体积比为0.5∶40(g/mL),膨胀石墨与过硫酸钾质量比为0.5∶8,反应时间为5.0 h的优化条件下,获得的石墨烯中寡层石墨烯约占90%,片径小于12μm的石墨烯约占88%;片径大于12μm的石墨烯约占12%;制备的石墨烯电导率为1.85×10^(4) S/m,灰分为1.01%。该方法制备的石墨烯氧化程度极低,可有效保留石墨完善的晶体结构。

Expanded graphite was obtained by microwave or high temperature expansion of graphite oxide,and the lamellae are easily peeled off.In this paper,graphene was prepared by chemical one-step exfoliation using expanded graphite as raw material,and the yield,electrical conductivity and defects of the product were characterized and analyzed.The results show that under the optimized conditions of mass volume ratio of expanded graphite to concentrated sulfuric acid was 0.5∶40,mass ratio of expanded graphite to potassium persulfate was 0.5∶8 and reaction time was 5 h,about 90%of the prepared products are graphene with few layers,and about 88%of the graphene with a diameter of less than 12μm;12%graphene sheet diameter was greater than 12μm.The obtained graphene conductivity was 1.85×10^(4) S/m,ash content was 1.01%.The graphene prepared by this method has an extremely low degree of oxidation and can effectively retain the perfect crystal structure of graphite.