Song Shuang, Xiang Jiongcan, Kang Hui, Yang Fengming
Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, China.
Institute of Advanced Study, Chengdu University, Chengdu 610106, China.
Molecules. 2025 Jan 7;30(2):206. doi: 10.3390/molecules30020206.
The photocatalytic oxidative coupling of methane (OCM) on metal-loaded one-dimensional TiO nanowires (TiO NWs) was performed. With metal loading, the electric and optical properties of TiO NWs were adjusted, contributing to the improvement of the activity and selectivity of the OCM reaction. In the photocatalytic OCM reaction, the 1.0 Au/TiO NW catalyst exhibits an outstanding CH production rate (4901 μmol g h) and selectivity (70%), alongside the minor production of CH and CH, achieving a total C-C hydrocarbon selectivity of 75%. In contrast, catalysts loaded with Ag, Pd, and Pt show significantly lower activity, with Pt/TiO NWs producing only CO, indicating a propensity for the deep oxidation of methane. The O-TPD analyses reveal that Au facilitates mild O adsorption and activation, whereas Pt triggers excessive oxidation. Spectroscopic and kinetic studies demonstrate that Au loading not only enhances the separation efficiency of photogenerated electron-hole pairs, but also promotes the generation of active oxygen species in moderate amounts, which facilitates the formation of methyl radicals and their coupling into CH while suppressing over-oxidation to CO. This work provides novel insights and design strategies for developing efficient photocatalysts.
在负载金属的一维TiO纳米线（TiO NWs）上进行了甲烷的光催化氧化偶联（OCM）反应。通过负载金属，TiO NWs的电学和光学性质得到了调节，这有助于提高OCM反应的活性和选择性。在光催化OCM反应中，1.0 Au/TiO NW催化剂表现出出色的CH生成速率（4901 μmol g h）和选择性（70%），同时CH和CH的生成量较少，总C-C烃选择性达到75%。相比之下，负载Ag、Pd和Pt的催化剂活性显著较低，Pt/TiO NWs仅生成CO，表明甲烷有深度氧化的倾向。O-TPD分析表明，Au有利于温和的O吸附和活化，而Pt引发过度氧化。光谱和动力学研究表明，负载Au不仅提高了光生电子-空穴对的分离效率，还促进了适量活性氧物种的生成，这有利于甲基自由基的形成及其偶联生成CH，同时抑制过度氧化生成CO。这项工作为开发高效光催化剂提供了新的见解和设计策略。
