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Strong metal‐support interactions (SMSI) featuring the formation of encapsulation overlayer around metal nanoparticles has drawn much attention in heterogeneous catalysis. Recent years, various novel SMSI phenomena have been observed and the nature of SMSI also has been revealed with the improvement of characterization techniques. Understanding the SMSI effect could deepen the insight into the structure‐activity relationship of metal‐supported catalysts, and rationally guide the design of special metal‐interface sites to manipulate catalytic behavior in chemical reaction. In this review, the research progress of SMSI and its application in heterogeneous COx hydrogenation are briefly surveyed, with emphasis on the advanced characterization, manipulation strategy and specific role of SMSI in Fischer‐Tropsch synthesis process, CO2 methanation and Reverse Water Gas Shift reaction. The current challenges and perspectives for the development of SMSI are also discussed. [ABSTRACT FROM AUTHOR]

Understanding the structures and reaction mechanisms of interfacial active sites in the Fisher-Tropsch synthesis reaction is highly desirable but challenging. Herein, we show that the ZrO2-Ru interface could be engineered by loading the ZrO2 promoter onto silica-supported Ru nanoparticles (ZrRu/SiO2), achieving 7.6 times higher intrinsic activity and ~45% reduction in the apparent activation energy compared with the unpromoted Ru/SiO2 catalyst. Various characterizations and theoretical calculations reveal that the highly dispersed ZrO2 promoter strongly binds the Ru nanoparticles to form the Zr-O-Ru interfacial structure, which strengthens the hydrogen spillover effect and serves as a reservoir for active H species by forming Zr-OH* species. In particular, the formation of the Zr-O-Ru interface and presence of the hydroxyl species alter the H-assisted CO dissociation route from the formyl (HCO*) pathway to the hydroxy-methylidyne (COH*) pathway, significantly lowering the energy barrier of rate-limiting CO dissociation step and greatly increasing the reactivity. This investigation deepens our understanding of the metal-promoter interaction, and provides an effective strategy to design efficient industrial Fisher-Tropsch synthesis catalysts. Understanding the structures of interfacial active sites is crucial in heterogeneous catalysis. Here the authors demonstrate that a ZrO2-Ru interface site significantly enhances reactivity in the Fischer-Tropsch to olefins process by altering the H-assisted CO dissociation route due to the presence of hydroxy species associated with Zr-OH*. [ABSTRACT FROM AUTHOR]

As a primary constituent of natural gas and shale gas, direct conversion of methane has attracted significant attention due to its potential to reduce energy consumption and CO2 emissions. Compared with thermal catalysis, photocatalysis has the capacity to transcend thermodynamic constraint and enable the conversion of sustainable solar energy into chemical energy under mild reaction condition, which contributes to optimize the utilization of methane. In this review, we undertake a comparative analysis of various strategies for photocatalytic methane conversion to syngas and chemicals, including photocatalytic reforming of methane, photocatalytic partial oxidation of methane and photocatalytic coupling of methane. The distinct reaction systems with corresponding catalysts and underlying mechanisms are expounded in detail to foster a profound comprehension of solar‐driven methane conversion. Finally, the challenges and prospectives in photocatalytic methane conversion are discussed. [ABSTRACT FROM AUTHOR]

The limited surface coverage and activity of active hydrides on oxide surfaces pose challenges for efficient hydrogenation reactions. Herein, we quantitatively distinguish the long-puzzling homolytic dissociation of hydrogen from the heterolytic pathway on Ga2O3, that is useful for enhancing hydrogenation ability of oxides. By combining transient kinetic analysis with infrared and mass spectroscopies, we identify the catalytic role of coordinatively unsaturated Ga3+ in homolytic H2 dissociation, which is formed in-situ during the initial heterolytic dissociation. This site facilitates easy hydrogen dissociation at low temperatures, resulting in a high hydride coverage on Ga2O3 (H/surface Ga3+ ratio of 1.6 and H/OH ratio of 5.6). The effectiveness of homolytic dissociation is governed by the Ga-Ga distance, which is strongly influenced by the initial coordination of Ga3+. Consequently, by tuning the coordination of active Ga3+ species as well as the coverage and activity of hydrides, we achieve enhanced hydrogenation of CO2 to CO, methanol or light olefins by 4-6 times. Zhu et al. report a quantitative and time-resolved analysis of hydrogen activation on Ga2O3, specifically shedding light on the long-standing puzzle of homolytic dissociation as opposed to the heterolytic pathway on oxides. [ABSTRACT FROM AUTHOR]

Syngas conversion is a useful technology for converting nonpetroleum carbon resources into chemicals such as olefins. Iron- and cobalt-based catalysts, as two major categories, have been extensively studied in Fischer–Tropsch synthesis to olefins (FTO) reactions. Although both iron and cobalt catalysts have shown distinct merits and shortcomings, they are also complementary in their properties and catalytic performances when combined with each other. Herein, Na-modified CoFe bimetallic catalysts were fabricated using a co-precipitation method. It was found that there was a synergistic effect between Co and Fe that promoted a CO dissociation rate and carburization, and an appropriate Co/Fe ratio was conducive to improvements in their catalytic performances. The desired olefins selectivity reached 66.1 C% at a CO conversion of 37.5% for a Co2Fe1 catalyst, while the methane selectivity was only 4.3 C%. In addition, no obvious deactivation was found after nearly 160 h, indicating their potential industrial application. [ABSTRACT FROM AUTHOR]