Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, Department of Chemistry, Liaocheng University, Liaocheng, 252059 Shandong, China.
Anal Chem. 2011 Dec 1;83(23):9100-6. doi: 10.1021/ac202136n. Epub 2011 Nov 4.
Separation and purification of graphene oxide (GO) prepared from chemical oxidation of flake graphite and ultrasonication by capillary electrophoresis (CE) was demonstrated. CE showed the ability to provide high-resolution separations of GO fractionations with baseline separation. The GO fractionations after CE were collected for Raman spectroscopy, atomic force microscopy, and transmission electron microscopy characterizations. GO nanoparticles (unexfoliated GO) or stacked GO sheets migrated toward the anode, while the thin-layer GO sheets migrated toward the cathode. Therefore, CE has to be performed twice with a reversed electric field to achieve a full separation of GO. This separation method was suggested to be based on the surface charge of the GO sheets, and a separation model was proposed. This study might be valuable for fabrication of GO or graphene micro- or nanodevices with controlled thickness.
从片状石墨的化学氧化和超声处理中制备的氧化石墨烯（GO）的分离和纯化通过毛细管电泳（CE）进行了演示。CE 表现出提供高分辨率 GO 级分分离的能力，具有基线分离。CE 后收集 GO 级分进行拉曼光谱、原子力显微镜和透射电子显微镜表征。GO 纳米颗粒（未剥离的 GO）或堆叠的 GO 片层朝着阳极迁移，而薄层 GO 片层朝着阴极迁移。因此，必须两次进行 CE 并反转电场以实现 GO 的完全分离。该分离方法基于 GO 片的表面电荷，并提出了一种分离模型。这项研究对于制造具有可控厚度的 GO 或石墨烯微纳器件可能具有重要价值。
