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Dry reforming of CH4/CO2 provides an attractive route to convert greenhouse gas into syngas; however, the resistance to sintering and coking of catalyst remains a fundamental challenge at high operation temperatures. Here we create active and durable metal–oxide interfaces in porous single‐crystalline (PSC) CeO2 monoliths with in situ exsolved single‐crystalline (SC) Ni particles and show efficient dry reforming of CH4/CO2 at temperatures as low as 450 °C. We show the excellent and durable performance with ≈20 % of CH4 conversion and ≈30 % of CO2 conversion even in a continuous operation of 240 hours. The well‐defined active metal–oxide interfaces, created by exsolving SC Ni nanoparticles from PSC NixCe1−xO2 to anchor them on PSC CeO2 scaffolds, prevent nanoparticle sintering and enhance the coking resistance due to the stronger metal–support interactions. Our work would enable an industrially and economically viable path for carbon reclamation, and the technique of creating active and durable metal–oxide interfaces in PSC monoliths could lead to stable catalyst designs for many challenging reactions. [ABSTRACT FROM AUTHOR]

Dry reforming of CH4/CO2 provides an attractive route to convert greenhouse gas into syngas; however, the resistance to sintering and coking of catalyst remains a fundamental challenge at high operation temperatures. Here we create active and durable metal–oxide interfaces in porous single‐crystalline (PSC) CeO2 monoliths with in situ exsolved single‐crystalline (SC) Ni particles and show efficient dry reforming of CH4/CO2 at temperatures as low as 450 °C. We show the excellent and durable performance with ≈20 % of CH4 conversion and ≈30 % of CO2 conversion even in a continuous operation of 240 hours. The well‐defined active metal–oxide interfaces, created by exsolving SC Ni nanoparticles from PSC NixCe1−xO2 to anchor them on PSC CeO2 scaffolds, prevent nanoparticle sintering and enhance the coking resistance due to the stronger metal–support interactions. Our work would enable an industrially and economically viable path for carbon reclamation, and the technique of creating active and durable metal–oxide interfaces in PSC monoliths could lead to stable catalyst designs for many challenging reactions. [ABSTRACT FROM AUTHOR]

In this work, the δ%Y–10%Co/MA (δ = 0, 1, 2, 3, and 5 wt%) catalysts synthesised by sequential incipient wetness impregnation were characterised and evaluated in CH 4 dry reforming. Superior catalytic performances were shown by 3 wt% Y 2 O 3 loading (CH 4 conversion = 85.8%, and CO 2 conversion = 90.5%), followed by 2 wt% > 5 wt% > 1 wt% > 0 wt% Y 2 O 3 loading. This result was attributed to the favorable catalytic properties of 3 wt%Y–10%Co/MA including small Co particle size, high Co dispersion, high amount of atomic ratio (Co/Al), and high number of lattice oxygen vacancies. The excess Y 2 O 3 addition (>3 wt%) led to inevitably blocked Co active sites and resulted in decreasing catalytic performance. The 3 wt% Y 2 O 3 promoter loading recorded the lowest carbon deposited (7.0%) due to the highest oxygen vacancies (78.1%) compared to 1, 2 and 5 wt% Y 2 O 3. Image 1 • Amount of Y 2 O 3 added on 10%Co/Mesoporous Alumina (Co/MA): 0, 1, 2, 3 and 5 wt%. • 3%Y–10%Co/MA exhibited small particle size, high dispersion, and high oxygen vacancy. • Activity: 3%Y–10%Co/MA > 2%Y–10%Co/MA > 5%Y–10%Co/MA > 1%Y–10%Co/MA > 10%Co/MA. • Highest activity of 3%Y–10%Co/MA credited to its favorable physicochemical properties. • Excess amount of Y 2 O 3 loading (>3%) covers the active site, thus lowering catalytic activity. [ABSTRACT FROM AUTHOR]

The dry reforming of shale gas (methane and ethane with an average ratio of 4 : 1) with carbon dioxide (DRS) is considered to be a promising way to produce syngas, which widens the utilization of shale gas and mitigates carbon dioxide emission. In this paper, Ce modified Ni‐based catalysts were developed and the corresponding catalytic performances for DRS were investigated with a fixed bed reactor. Results showed that the catalyst containing 5 wt% of Ni and 5 wt% of Ce performed a best catalytic effect, including the selectivity of syngas and the carbon resistance performance, which is due to the good metal dispersion, strong interaction between Ni and Ce, and the formation of Ni‐CeOx solid solution. The electron transfer between Ni and Ce, substitution of Ni for Ce, and the sequential oxygen vacancies or defects, play significant roles in activating CH4, C2H6 and CO2. The conversion of reactant gas increased with temperature, while the selectivity of syngas is little affected with temperature. In addition, the desired catalyst containing 5 wt% of Ni and 5 wt% of Ce showed good stability in the long‐time operation, which indicates that the Ce modified Ni‐based catalyst is a promising one for the dry reforming of shale gas. High fives! The catalyst 5Ni‐5Ce exhibits the best catalytic performance in the dry reforming of shale gas and CO2. The introduction of Ce creates strong interaction between Ni and Ce, which enhances the electron transfer between them. And the substitution of Ni for Ce produces oxygen vacancies and defects, which can accelerate the adsorption and activation of the reactant gases molecule, further promoting the reaction. [ABSTRACT FROM AUTHOR]

Abstract: Dry reforming of methane has been systematically investigated over a series of x‐Co@SiO2‐y catalysts where x is the Co particle size ranging from 11.1 to 121.3 nm while y denotes the silica shell thickness ranging from 6.0 to 21.9 nm. Various techniques including TEM, XRD, H2‐TPR/‐TPD, XPS, BET, O2‐TPO, TG, and H2‐TPSR‐MS were employed to characterize physicochemical properties of catalysts. H2‐TPR and XPS results indicate that the core–shell interaction is dependent on the core size: the smaller the Co particle size is; the stronger the core–shell interaction. The investigations employing H2‐TRSR‐MS and XPS on the spent catalysts demonstrated that a fraction of metallic Co was re‐oxidized on a large‐core catalyst such as 121.3‐Co@SiO2‐72.2 during the reaction, and such oxidation leads to lower catalytic activity and stability. O2‐TPO results indicated that the catalyst with smaller core size caused significant coking. TG analysis together with TEM investigation on the used samples suggested that carbon deposition is notably core‐size‐dependent and responsible for deactivation of the small‐core catalyst. Among various core–shell structured catalysts, 27.8‐Co@SiO2‐14.3 showed superior activity and durability, owing to the well‐balanced property between coking and anti‐oxidation of Co cores. [ABSTRACT FROM AUTHOR]