Abstract Titanium dioxide modified with graphene oxide (GO/TiO2) nanocomposite thin films were prepared on glass substrates by a sol-gel route using the dip coating technique for photocatalytic applications. The graphene oxide powders, fabricated through a modified Hummers' method, and the GO/TiO2 thin films were characterized by electron microscopy, XRD, Raman and UV-VIS spectroscopy to evaluate their structural, morphological and optical properties. The energy bandgap estimated for the thin films is in the range of 3.38–3.45 eV after an annealing at 450 °C; while the transmittance and the Raman intensity decreased significantly by increasing the amount of GO. The photocatalytic activity of the GO/TiO2 thin films, investigated by the blenching of methylene blue, showed a significant increment with the addition of GO; furthermore, the films exhibited potential applications in the photoreduction of CO2, in which a methanol production of 68.443 μmol cm−2 was observed after 5 h of reaction in the presence of UV light.

中文翻译：

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用于光催化应用的溶胶-凝胶法合成和表征氧化石墨烯 - TiO2 薄膜

摘要 使用浸涂技术在玻璃基板上通过溶胶-凝胶途径制备了氧化石墨烯 (GO/TiO2) 纳米复合薄膜改性的二氧化钛，用于光催化应用。通过改进的 Hummers 方法制备的氧化石墨烯粉末和 GO/TiO2 薄膜通过电子显微镜、XRD、拉曼和 UV-VIS 光谱进行表征，以评估它们的结构、形态和光学特性。在 450 °C 下退火后，估计薄膜的能带隙在 3.38-3.45 eV 范围内；而通过增加 GO 的量，透光率和拉曼强度显着降低。通过亚甲基蓝的漂白研究GO/TiO2薄膜的光催化活性随着GO的加入而显着增加；此外，