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In recent years, CO2 reforming of methane (dry reforming of methane, DRM) has become an attractive research area because it converts two major greenhouse gasses into syngas (CO and H2), which can be directly used as fuel or feedstock for the chemical industry. Ni‐based catalysts have been extensively used for DRM because of its low cost and good activity. A major concern with Ni‐based catalysts in DRM is severe carbon deposition leading to catalyst deactivation, and a lot of effort has been put into the design and synthesis of stable Ni catalysts with high carbon resistance. One effective and practical strategy is to introduce a second metal to obtain bimetallic Ni‐based catalysts. The synergistic effect between Ni and the second metal has been shown to increase the carbon resistance of the catalyst significantly. In this review, a detailed discussion on the development of bimetallic Ni‐based catalysts for DRM including nickel alloyed with noble metals (Pt, Ru, Ir etc.) and transition metals (Co, Fe, Cu) is presented. Special emphasis has been provided on the underlying principles that lead to synergistic effects and enhance catalyst performance. Finally, an outlook is presented for the future development of Ni‐based bimetallic catalysts.

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With wide availability, high thermal stability and high specific surface area, silica-based micro- and mesoporous materials show promising performance for dry reforming of methane reaction, boosting efficient and sustainable utilization of greenhouse gases.

This article provides a critical review of Ni-based catalysts employed in high temperature and ultra-high temperature water gas shift reaction (WGS) for hydrogen production and methane suppression. The promotional role of nature and type of active metal and support for WGS reaction is discussed with respect to activity and selectivity. This review mainly covers the recent strategic catalytic formulations like promotion with alkali metals, alloying with another metal and core@-shell-like structures for suppressing methanation during WGS reaction. The change in nature and strength of CO adsorption over modified Ni-surfaces is discussed using available in situ CO-DRIFTS results. The various WGS reaction and CO methanation pathways are also presented together with insights gained from computational DFT studies.[a] Dr.

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The involvement of surface hydroxyl species in controlling methanol selectivity for a CO 2 hydrogenation reaction was investigated over Cu-phyllosilicate (Cu-SiO 2P ) catalysts prepared by a urea-assisted hydrothermal synthesis method. The role of hydroxyls involvement was investigated by treating the Cu-SiO 2P catalyst between 225 and 350 °C in H 2 gas. The presence of Cu-containing phyllosilicate structures in Cu-SiO 2P catalysts was confirmed through TEM and XPS analyses. As evidenced by in situ diffuse reflectance infrared fourier transform spectroscopy (DRIFTS) and X-ray absorption spectroscopy, Cu + centers are dominant surface species for Cu in Cu-SiO 2P catalysts during the hydrogenation reaction. Also, bidentate formate species are the prominent intermediates to direct methanol formation via methoxy intermediate species. The hydroxyl intervention in CO 2 hydrogenation for a hydroxyl-abundant Cu-SiO 2P catalyst reduced at 225 °C is confirmed by the appearance of a new band at 2944 cm −1 (−C−H) by high-pressure in situ DRIFTS CO 2 hydrogenation experiments. H 2 /CO-TPR revealed the uniformity and presence of surface hydroxyls in Cu-SiO 2P catalysts. The best catalyst Cu-SiO 2P reduced at 225 °C gave a stable CO 2 conversion of 3.5% and a methanol yield of 140 mg MeOH/g-cat.h (a methanol selectivity of 77%) at 225 °C and 3 MPa pressure for a 24 h reaction time. The presence of hydroxyls generated due to partial reduction of the Cu-SiO 2P catalyst and surface enriched with Cu + species could be the reasons for its superior catalytic performance.