Here, the elaboration of few layer graphene/TiO₂ photocatalytic composites (FLG/TiO₂) with FLG loadings from 0.5 to 11 wt % is presented. Contrary to the commonly used (reduced) graphene oxide obtained by long and harsh condition synthesis, FLG was synthesized by a simple, fast, efficient, and eco-friendly exfoliation method. The enhancement of defective/functionalized site density for the attachment of TiO₂ species was achieved via the calcination process at 450 °C. The nanocomposites were evaluated toward H₂ production from methanol under artificial solar light irradiation, without the use of a co-catalyst. It was observed that the best activities are provided by the composites with the lowest loading: 0.5 and 1.0 wt % FLG/TiO₂ that are 2–3 times more efficient than reference and commercial TiO₂. The photocatalytic activity of the composites was correlated to their surface area, morphological, structural, optical properties, and kinetics of free electron mobility properties. The enhanced activity is attributed to a higher surface area, better photogenerated charge separation thanks to electrons’ delocalization and trapping onto graphene layers well interfaced with TiO₂ nanoparticles but also to additional FLG visible light absorption properties and charge carriers’ generation. The impact of enhanced FLG edge defects/functionalities is reflected as well via selected analysis and hydrogen generation.

中文翻译：

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少量层状石墨烯/ TiO ₂复合材料可增强甲醇驱动的太阳能驱动H _2的生产

在此，提出了具有0.5至11 wt％的FLG含量的几层石墨烯/ TiO ₂光催化复合材料（FLG / TiO ₂）的制备。与通过长时间和苛刻条件合成获得的常用（还原）氧化石墨烯相反，FLG是通过简单，快速，高效且环保的剥落方法合成的。通过在450°C下的煅烧过程，可以提高缺陷/官能化位点密度对TiO ₂物种的附着能力。在不使用助催化剂的情况下，在人工太阳光照射下评估了纳米复合材料对甲醇产生H _2的影响。观察到，具有最低负载量的复合材料提供了最好的活性：0.5和1.0 wt％的FLG / TiO_2的效率是参考和商用TiO _2的2-3倍。复合材料的光催化活性与它们的表面积，形态，结构，光学性质和自由电子迁移性质的动力学相关。增强的活性归因于更高的表面积，更好的光生电荷分离，这要归功于电子的离域作用和捕获在与TiO ₂纳米颗粒良好交界的石墨烯层上的作用，还归功于额外的FLG可见光吸收性能和电荷载流子的产生。增强的FLG边缘缺陷/功能的影响也通过选定的分析和氢气产生得到反映。