论文标题
关于FLG /TIO $ _2 $纳米复合材料中几层石墨烯（FLG）氧化蚀刻的演变。 C1S X射线光发射光谱中的界面偶极子签名和化学位移
On the evolution of oxidative etching of few layer graphene (FLG) in FLG /TiO$_2$ nanocomposites. Interfacial dipole signature and chemical shift in C1s X-ray photoemission spectra
论文作者
论文摘要
我们介绍了FLG/TIO $ _2 $杂种在FLG边缘化学/形态学上的氧化蚀刻效果，还涉及TIO $ _2 $ nps的催化活性。根据XPS和TGA分析，氧化度很大程度上取决于TIO $ _2 $：FLG比率。通过Sol-Gel方法和原位氧化制备了两个系列FLG/TIO $ _2 $混合体，可以正确描述和区分C1S XPS中的化学成分，核心移位和电荷分布，尖端为参考。由于样品和不定碳参考的C1S峰重叠，这种分析在碳材料中具有挑战性。我们声称形成了界面偶极子作为可能的直接签名，从Tio $ _2 $转移到FLG。测量了C1S（SP $^2 $ C）的下移最高1.4 eV，并在复合材料中确定了非SP $^2 $ C的贡献。与氧化相关的修改由TEM/SEM观测值支持，并指的是机械混合成分中的非催化氧化和氧化。 关键字：氧化蚀刻，石墨烯边缘，Tio $ _2 $催化剂，界面偶极子，XPS，电荷转移
We present the effect of oxidative etching in FLG/TiO$_2$ hybrids on FLG edges chemistry/morphology addressing also the catalytic activity of TiO$_2$ NPs. According to the XPS and TGA analysis the oxidation degree strongly depends on TiO$_2$:FLG ratio. The preparation of two series of FLG/TiO$_2$ hybrids via sol-gel method and in-situ oxidation permitted to correctly describe and distinguish the chemical composition, core shift and charge distribution in C1s XPS with Tip peak as reference. Such analysis is challenging in carbon materials due the overlapping of C1s peaks from the sample and adventitious carbon reference. We claim the formation of interfacial dipole as possible direct signature of charge transfer from TiO$_2$ to FLG. A downward shift of C1s (sp$^2$C) up to 1.4 eV is measured and contributions of non sp$^2$C are determined in the composites. The modifications related to the oxidation are supported by TEM/SEM observations, and referred to non-catalytic oxidation and oxidation in mechanically mixed components. KEYWORDS: oxidative etching, graphene edges, TiO$_2$ catalyst, interfacial dipole, XPS, charge transfer
