Feng Zhenbao, Lin Yangming, Tian Cunwei, Hu Haiquan, Su Dangsheng
School of Physical Science and Information Technology, Shandong Key Laboratory of Optical Communication Science and Technology, Liaocheng University, 252059, Liaocheng, China.
Max-Planck Institute for Chemical Energy Conversion, 45470, Mülheim, Germany.
Sci Rep. 2019 Mar 7;9(1):3784. doi: 10.1038/s41598-019-40529-2.
The electron momentum density and sp/sp ratio of carbon materials in the thermal transformation of detonation nanodiamonds (ND) into carbon nano-onions are systematically studied by electron energy-loss spectroscopy (EELS). Electron energy-loss near-edge structures of the carbon K-ionization in the electron energy-loss spectroscopy are measured to determine the sp content of the ND-derived samples. We use the method developed by Titantah and Lamoen, which is based on the ability to isolate the π spectrum and has been shown to give reliable and accurate results. Compton profiles (CPs) of the ND-derived carbon materials are obtained by performing EELS on the electron Compton scattering region. The amplitude of the CPs at zero momentum increases with increasing annealing temperature above 500 °C. The dramatic changes occur in the temperature range of 900-1300 °C, which indicates that the graphitization process mainly occurs in this annealing temperature region. Our results complement the previous work on the thermal transformation of ND-derived carbon onions and provide deeper insight into the evolution of the electronic properties in the graphitization process.
通过电子能量损失谱（EELS）系统地研究了爆轰纳米金刚石（ND）热转化为碳纳米洋葱过程中碳材料的电子动量密度和sp/sp比。测量电子能量损失谱中碳K电离的电子能量损失近边结构，以确定ND衍生样品的sp含量。我们使用了由Titantah和Lamoen开发的方法，该方法基于分离π光谱的能力，并且已被证明能给出可靠且准确的结果。通过在电子康普顿散射区域进行EELS，获得了ND衍生碳材料的康普顿轮廓（CPs）。在零动量处CPs的振幅随着退火温度高于500°C而增加。在900 - 1300°C的温度范围内发生了显著变化，这表明石墨化过程主要发生在这个退火温度区域。我们的结果补充了之前关于ND衍生碳洋葱热转化的工作，并为石墨化过程中电子性质的演变提供了更深入的见解。
