Abstract Graphene holds promise for the development of advanced materials from battery electrodes to sensors to structural composites. However, the current preparation methods of graphene rely on long-time oxidation where particularly hazardous materials are involved. We herein report a simple, cost-effective approach to scalable preparation of solution-processible yet high-structural integrity graphene, by heating a mixture of graphite, sulfuric acid and potassium persulfate at 70 °C for 7 min. The obtained graphene platelets have average thickness of 3.88 ± 0.80 nm and a lateral dimension below 2 μm, with a Raman ID/IG of 0.06. As measured by a 4-point probe method, a graphene platelet film exhibits surface resistance of 0.70 ± 0.10 Ω/sq, corresponding to electrical conductivity of 1618.12 ± 261.56 S/cm. The as-prepared platelets have carboxyl, epoxide and hydroxyl groups on the surface, and thus the functionalized graphene platelets should be compatible with many polymers. The platelets can suspend in ethanol at 1 mg/ml for up to 3 h.

中文翻译：

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功能化石墨烯薄片的低温快速制备

摘要 石墨烯有望用于开发从电池电极到传感器再到结构复合材料的先进材料。然而，目前石墨烯的制备方法依赖于长时间氧化，其中涉及特别危险的材料。我们在此报告了一种简单、经济高效的方法，通过在 70°C 下加热石墨、硫酸和过硫酸钾的混合物 7 分钟，可扩展制备可溶液加工但具有高结构完整性的石墨烯。获得的石墨烯片的平均厚度为 3.88 ± 0.80 nm，横向尺寸低于 2 μm，拉曼 ID/IG 为 0.06。通过 4 点探针法测量，石墨烯薄片薄膜的表面电阻为 0.70 ± 0.10 Ω/sq，对应于 1618.12 ± 261.56 S/cm 的电导率。制备的血小板具有羧基，表面上的环氧化物和羟基，因此功能化的石墨烯片应与许多聚合物相容。血小板可以以 1 毫克/毫升的浓度悬浮在乙醇中长达 3 小时。