Sidorowicz Agnieszka, Wicht Thomas, Stöger-Pollach Michael, Licheri Roberta, Cao Giacomo, Concas Alessandro, Rupprechter Günther
Interdepartmental Centre of Environmental Engineering and Sciences, University of Cagliari, Cagliari, 09123 Cagliari, Italy.
Institute of Materials Chemistry, TU Wien, Getreidemarkt 9/BC, Vienna, 1060 Vienna, Austria.
ACS Catal. 2025 Aug 19;15(17):15261-15278. doi: 10.1021/acscatal.5c04285. eCollection 2025 Sep 5.
Controlling the selectivity of CO hydrogenation to produce value-added fuels and chemicals is an actual challenge in catalysis research. The exact mechanisms underlying selectivity control often remain poorly understood, slowing the design of more efficient catalysts. In this study, we investigated RuO nanoparticles supported on MXene or TiO for CO hydrogenation at atmospheric pressure. Microalgal extracts were incorporated in the synthesis to explore their influence on catalyst properties, such as surface area, morphology, and elemental distribution. Although lower surface area and less uniform RuO dispersion were observed on MXenes than on TiO, after reductive pretreatment Ru/MXene exhibited superior catalytic activity, demonstrating that its unique textural properties and active site availability compensated for the lower surface area. A reducibility study revealed that MXene-supported catalysts undergo a more complex reduction process than those with TiO as the support. Additionally, bridge adsorption sites on MXene likely contributed to the enhanced CO hydrogenation activity, whereas TiO seemed to present a twin CO binding environment. Higher Ru loading on MXene increased the methane selectivity and conversion, whereas lower loading favored CO formation, highlighting the importance of optimizing catalyst loading. diffuse reflectance infrared Fourier transform spectroscopy analysis revealed the critical role of methoxy intermediates in affecting the catalytic pathway, suggesting the potential for tuning synthesis conditions to improve yields. A partial encapsulation of Ru on MXene enhances the catalytic performance, while the stronger SMSI effect on TiO leads to complete encapsulation, reducing the catalytic efficiency. The findings underscore the promise of MXene as a support material for metal catalysts in CO hydrogenation toward environmentally friendly fuel production.
控制一氧化碳加氢以生产增值燃料和化学品的选择性是催化研究中的一个实际挑战。选择性控制背后的确切机制往往仍未得到充分理解，这减缓了更高效催化剂的设计。在本研究中，我们研究了负载在MXene或TiO上的RuO纳米颗粒在大气压下用于一氧化碳加氢的情况。在合成过程中加入了微藻提取物，以探索它们对催化剂性能的影响，如表面积、形态和元素分布。尽管在MXene上观察到的表面积比在TiO上低，且RuO的分散性也较差，但经过还原预处理后，Ru/MXene表现出优异的催化活性，这表明其独特的结构性质和活性位点可用性弥补了较低的表面积。一项还原研究表明，负载在MXene上的催化剂经历的还原过程比以TiO为载体的催化剂更复杂。此外，MXene上的桥式吸附位点可能有助于提高一氧化碳加氢活性，而TiO似乎呈现出双一氧化碳结合环境。在MXene上较高的Ru负载量增加了甲烷的选择性和转化率，而较低的负载量则有利于一氧化碳的生成，这突出了优化催化剂负载量的重要性。漫反射红外傅里叶变换光谱分析揭示了甲氧基中间体在影响催化途径中的关键作用，这表明调整合成条件以提高产率具有潜力。Ru在MXene上的部分包覆提高了催化性能，而在TiO上更强的金属-载体强相互作用效应导致完全包覆，降低了催化效率。这些发现强调了MXene作为金属催化剂载体材料在一氧化碳加氢生产环境友好型燃料方面的前景。
