超临界CO2流体剥离膨胀石墨制备石墨烯

Graphene was Prepared by Stripping Expanded Graphite with Supercritical CO2 Fluid

以膨胀石墨为原料,利用超临界CO2流体的方法,在高温高压的条件下,通过插层剥离膨胀石墨然后快速卸压来制备石墨烯。研究了超声时间、反应时间、反应温度和压力对石墨烯产率的影响;利用X射线衍射仪、扫描电子显微镜及透射电子显微镜对膨胀石墨及所制备石墨烯进行结构和形貌表征,通过四探针测试仪对石墨烯的电导率进行测试。结果表明:采用超临界CO2流体的方法制备石墨烯的最佳工艺为:超声时间为2 h,反应时间为3 h,反应温度为60℃,压力为14 MPa;制备出层数在10层以内石墨烯,石墨烯片层大小为15μm左右,厚度为5 nm左右;石墨烯的平均电导率在105 S/m左右。

With expanded graphite as raw material,using the method of supercritical CO2 fluid under high temperature and high pressure conditions,by intercalating stripping expanded graphite and then quick pressure relief to prepare graphene.The effects of ultrasonic time,reaction time,reaction temperature and pressure on graphene yield were studied.The structure and morphology of the expanded graphite and the prepared graphene were characterized by X-ray diffractometer,scanning electron microscope and transmission electron microscope.The electrical conductivity of graphene was tested with a four-probe tester.The results show that:The optimal preparation process of graphene by supercritical CO2 fluid was as follows:ultrasonic time of 2 h,reaction time of 3 h,reaction temperature of 60℃,pressure of 14 MPa.The number of graphene layers was less than 10.The size of the graphene sheet was about 15 microns and the thickness was about 7 nm.The average electrical conductivity of graphene is around 105 S/m.