Lately, the optical properties of Graphene Oxide (GO) and Reduced Graphene Oxide (RGO) films have been studied in the ultraviolet and visible spectral range. However, the accurate optical properties in the extended near-infrared and mid-infrared range have not been published yet. In this work, we report a Variable Angle Spectroscopic Ellipsometry (VASE) characterization of GO thin films dip-coated on SiO₂/Si substrates and thermally reduced GO films in the 0.38–4.1 eV photon energy range. Moreover, the optical properties of RGO stabilized with poly(sodium 4-styrenesulfonate) (PSS) films dip-coated on SiO₂/Si substrates are studied in the same range for the first time. The Lorentz optical models fit well with the experimental data. In addition, the morphological properties of the samples were investigated by Scanning Electron Microscopy (SEM) analysis.

中文翻译：

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聚（4-苯乙烯磺酸钠）稳定的氧化石墨烯的可变角光谱椭圆仪表征

最近，已经研究了在紫外和可见光谱范围内氧化石墨烯（GO）和还原氧化石墨烯（RGO）薄膜的光学特性。但是，尚未发布在扩展的近红外和中红外范围内的准确光学特性。在这项工作中，我们报告了在SiO ₂ / Si衬底上浸涂的GO薄膜和在0.38–4.1 eV光子能量范围内热还原的GO薄膜的可变角度光谱椭圆仪（VASE）表征。此外，用浸涂在SiO ₂上的聚（4-苯乙烯磺酸钠）（PSS）薄膜稳定的RGO的光学性能首次在相同范围内研究/ Si基板。洛伦兹光学模型与实验数据非常吻合。另外，通过扫描电子显微镜（SEM）分析研究了样品的形态学特性。