Graphite oxide (GO) was prepared from liquid oxidation based on Hummers method and the graphene was then prepared using sodium borohydride to reduce the exfoliated graphite oxide by ultrasonication during which moderate sodium dodecyl benzene sulfonate (SDBS) was added into the suspension to reduce the agglomeration among the graphene layers and to obtain a stable graphene suspension. The as-prepared graphene was characterized by X-ray diffraction (XRD), Raman spectroscopy (RS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM). XRD results show that the crystal structures are different among graphite, graphite oxide, and graphene. SEM and TEM images show that graphene possesses a gridding structure, a smooth surface, and few defects. AFM analysis indicates that the thickness of the single layer graphene is about 1.3 nm while there are still a few double layers in the sample. The BET specific surface area of the graphene was about 1206 m2·g-1 and its H2 adsorption properties were investigated under high pressure. The samples prepared by liquid oxidation-reduction were compared with that prepared by the improved liquid oxidation-reduction method, which indicates that the addition of SDBS effectively reduces agglomeration among the graphene layers and this generates high quality graphene. The adsorption capacities of H2 on graphene at 25 and 55 °C reached 1.7%(w) and 1.1 %(w), respectively, which are much higher than that reported previously.%以液相氧化还原法为基础,并在分散剂十二烷基苯磺酸钠(SDBS)作用下制备得到高质量石墨烯,有效避免了在此过程中石墨烯大量团聚的现象.采用X射线衍射(XRD)、拉曼光谱(RS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和原子力显微镜(AFM)等分析手段对石墨烯样品进行了表征.XRD结果体现了石墨、氧化石墨和石墨烯晶型结构的区别;SEM和TEM结果显示石墨烯呈网格状,表面平整,缺陷少;AFM分析表明样品中单层石墨烯厚度约为1.3 nm,同时也存在少许双层结构.BET测试法得到石墨烯的比表面积高达1206 m2·g-1,考察了石墨烯在高压条件下对H2的吸附性能.通过对方法改进前后所制备的石墨烯样品进行比较,结果表明,十二烷基苯磺酸钠的加入有效地减小了石墨烯的大量团聚,且得到了高质量的石墨烯.在25和55℃条件下,高质量石墨烯对氢气的吸附量分别达到1.7％(w)和1.1％(w),比之前研究结果有了很大提高.
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