一种廉价高效石墨烯量子点（GQDs）制备新方法研究

Owing to the quantum confinement and edge effects, graphene quantum dots (GQDs), a new nanophase material, have potential application in many fields. However, it is hard to prepare GQDs in a cheap and effective way until now，which limit its real application. In our research process, we found that GQDs can be effectively generated from graphene oxide (GO, prepared according to improved Hummers method by using electron beam irradiated graphite as the raw material) under the co-effect of initiator, crossing agents and acrylic acid. The mass yield was found to be 20% which is much higher than the reported results. With the intention to further improve the mass yield and realize the cheap and effective production of GQDs, the steps of the whole process are carefully studied in present project. The conditions used for deeply oxide graphite will be determined; the effect of the agents and their proper amount on GQDs generation will be confirmed; the effect of ultrasonic time and temperature on the mass yield of GQDs will also studied. Different sized GQDs will be prepared and the mechanism involved in the GQDs generation will be de deduced from the proper calculation. On the basis of the above results, the toxicity of different sized GQDs on Hela cell will be studied, which will give the fundamental data of our GQDs in bioimaging application.

石墨烯量子点（GQDs）作为一种新兴的纳米材料，因量子限域效应和边界效应，在多个领域具有广泛的应用前景，但目前大批量廉价制GQDs仍未解决，这就限制了其在实际中的应用。本项目组在研究中发现，利用电子束辐照石墨制备的氧化石墨烯（GO），在引发剂、交联剂和丙烯酸的作用下可以生成GQDs，且量子点质量产率在20%以上，远高于现有结果。本项目拟在已有工作基础上，以进一步提高GQDs的质量产率，实现其真正廉价高效制备为目标，通过对量子点制备过程中各个实验步骤的详细研究，更深刻的理解此GQDs制备新方法的工艺过程，找到充分氧化辐照石墨所需的条件，发现各试剂在GQDs制备过程中的作用和合适的加入量；确定各外部条件对量子点质量产率的影响及石墨辐照剂量与GQDs大小的对应关系，结合理论计算揭示GQDs的生成机理，在此基础上，开展不同大小GQDs对细胞的毒理研究，为所制备量子点在生物成像中的应用提供数据支持。

石墨烯量子点（GQDs）是一种新兴的碳基纳米材料，因其具有良好的发光性能，在生物成像/治疗、催化、太阳能电池等多个领域具有广泛的应用前景，但现有方法制备GQDs的产额均较低，使得GQDs价格昂贵，限制了其在实际中的应用。为了提高GQDs的产额，得到一种廉价高效的制备GQDs的新方法，本项目以高能电子束辐照过石墨为原料，结合强酸氧化和化学接枝来获得GQDs。详细研究了各反应步骤中可能影响GQDs产额的因素，获得产额较高GQDs的制备工艺。利用此工艺，得到 GQDs的产额可高达30%以上，高于现有文献结果。另外，进行了不同辐照剂量下GQDs的制备研究，发现所得GQDs产额随辐照剂量增加而增大。本项目研究工作的开展，得到了一种廉价高效制备GQDs的新工艺，将推动GQDs在实际中的应用。