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Dalian Institute of Chemical Physics discovers the mechanism by which the metal-carrier interface regulates CO dissociation in Fischer-Tropsch synthesis. Author/Source: Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Date: June 26, 2020. Clicks: 62. Recently, Researcher Huang Yanqiang and Academician Zhang Tao’s team from the Catalysis and New Materials Laboratory at the Dalian Institute of Chemical Physics made progress in understanding the mechanism by which CO dissociation is regulated in Fischer-Tropsch synthesis. The study found that the TiOx coating formed on Ru nanoparticles (NPs) during the reduction process can directly participate in the dissociation of C-O bonds, thereby significantly enhancing their activity in Fischer-Tropsch synthesis. The Fischer-Tropsch synthesis reaction can convert non-petroleum resources (coal, natural gas, biomass, etc.) into fuels or chemicals with high added value through syngas, providing a technical pathway for the development of alternative energy sources. In the Fischer-Tropsch synthesis reaction, the step in which CO dissociates and is further hydrogenated to form CHx intermediate species is crucial; this generally occurs on the surfaces of Fe, Co, and Ru metals, among which Ru exhibits the best reaction performance. However, Ru-based catalysts exhibit a significant size effect; only Ru NPs around 8 nm possess high Fischer-Tropsch reaction activity, which severely reduces the efficiency of using the precious metal Ru. It is of great significance to develop highly dispersed and highly active Ru-based Fertro synthesis catalysts. Taking advantage of the fact that rutile-type RuO2 shares the same crystal structure as TiO2 and exhibits high lattice compatibility, the team successfully synthesized highly dispersed and stable Ru/TiO2 catalysts, in which the Ru NPs had a size of around 2 nm, and no significant change in their size occurred after reduction at 600 °C. By adjusting the reduction temperature of the catalyst, the team achieved controllable regulation of the degree of strong interaction between the metal and the support, thereby obtaining Ru/TiO2 catalysts with different metal-support interface structures. Studies have shown that, under the appropriate coordination at the metal-support interface, Ru NPs with a size of about 2 nm can exhibit excellent Fischer-Tropsch reaction activity under mild conditions (160°C), with a TOF value that is the highest reported in current literature. Through various characterization techniques combined with theoretical calculations, it was found that the TiOx coating formed due to the strong interaction between the metal and the support can directly participate in the dissociation of C-O bonds, thereby significantly enhancing the Fischer-Tropsch activity of Ru-based catalysts. This work not only reveals the catalytic mechanism of the strong metal-support interaction in the Fischer-Tropsch synthesis reaction, but also provides new insights for the design of other highly dispersed metal catalysts. The research findings were published in Nature Communications. This work was supported by the **Key Research and Development Program – Nanotechnology Focus Project**, the **Outstanding Young Scientist Fund**, and the Chinese Academy of Sciences’ Strategic Priority Research Program B “Principles and Measurements for the Precise Construction of Functional Nanosystems”.