Permatasari Fitri Aulia, Aimon Akfiny Hasdi, Iskandar Ferry, Ogi Takashi, Okuyama Kikuo
Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Bandung 40132, Indonesia.
Research Center for Nanoscience and Nanotechnology, Institut Teknologi Bandung, Bandung 40132, Indonesia.
Sci Rep. 2016 Feb 15;6:21042. doi: 10.1038/srep21042.
Graphene quantum dots (GQDs) containing N atoms were successfully synthesized using a facile, inexpensive, and environmentally friendly hydrothermal reaction of urea and citric acid, and the effect of the GQDs' C-N configurations on their photoluminescence (PL) properties were investigated. High-resolution transmission electron microscopy (HR-TEM) images confirmed that the dots were spherical, with an average diameter of 2.17 nm. X-ray photoelectron spectroscopy (XPS) analysis indicated that the C-N configurations of the GQDs substantially affected their PL intensity. Increased PL intensity was obtained in areas with greater percentages of pyridinic-N and lower percentages of pyrrolic-N. This enhanced PL was attributed to delocalized π electrons from pyridinic-N contributing to the C system of the GQDs. On the basis of energy electron loss spectroscopy (EELS) and UV-Vis spectroscopy analyses, we propose a PL mechanism for hydrothermally synthesized GQDs.
通过尿素和柠檬酸的简便、廉价且环境友好的水热反应成功合成了含氮原子的石墨烯量子点（GQDs），并研究了GQDs的C-N构型对其光致发光（PL）性质的影响。高分辨率透射电子显微镜（HR-TEM）图像证实这些量子点呈球形，平均直径为2.17 nm。X射线光电子能谱（XPS）分析表明，GQDs的C-N构型对其PL强度有显著影响。在吡啶型氮含量较高而吡咯型氮含量较低的区域获得了增强的PL强度。这种增强的PL归因于来自吡啶型氮的离域π电子对GQDs的C体系有贡献。基于能量损失谱（EELS）和紫外-可见光谱分析，我们提出了水热合成GQDs的PL机制。
