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Different Co contents were used to tune bimetallic Pt–Co nanoparticles with a diameter of 8 nm, resulting in Pt:Co ratios of 3.54, 1.51, and 0.96. These nanoparticles were then applied to the MCF-17 mesoporous silica support. The synthesized materials were characterized with HR-TEM, HAADF-TEM, EDX, XRD, BET, ICP-MS, in situ DRIFTS, and quasi in situ XPS techniques. The catalysts were tested in a thermally induced reverse water–gas shift reaction (CO2:H2 = 1:4) at atmospheric pressure in the 200–700 °C temperature range. All bimetallic Pt–Co particles outperformed the pure Pt benchmark catalyst. The nanoparticles with a Pt:Co ratio of 1.51 exhibited 2.6 times higher activity and increased CO selectivity by 4% at 500 °C. Experiments proved that the electron accumulation and alloying effect on the Pt–Co particles are stronger with higher Co ratios. The production of CO followed the formate reaction pathway on all catalysts due to the face-centered-cubic structure, which is similar to the Pt benchmark. It is concluded that the enhanced properties of Co culminate at a Pt:Co ratio of 1.51 because decreasing the ratio to 0.96 results in lower activity despite having more Co atoms available for the electronic interaction, resulting in the lack of electron-rich Pt sites. [ABSTRACT FROM AUTHOR]

The implementation of supported metal catalysts heavily relies on the synergistic interactions between metal nanoparticles and the material they are dispersed on. It is clear that interfacial perimeter sites have outstanding skills for turning catalytic reactions over, however, high activity and selectivity of the designed interface‐induced metal distortion can also obtain catalysts for the most crucial industrial processes as evidenced in this paper. Herein, the beneficial synergy established between designed Pt nanoparticles and MnO in the course of the reverse water gas shift (RWGS) reaction resulted in a Pt/MnO catalyst having ≈10 times higher activity compared to the reference Pt/SBA‐15 catalyst with >99 % CO selectivity. Under activation, a crystal assembly through the metallic Pt (110) and MnO evolved, where the plane distance differences caused a mismatched‐row structure in softer Pt nanoparticles, which was identified by microscopic and surface‐sensitive spectroscopic characterizations combined with density functional theory simulations. The generated edge dislocations caused the Pt lattice expansion which led to the weakening of the Pt−CO bond. Even though MnO also exhibited an adverse effect on Pt by lowering the number of exposed metal sites, rapid desorption of the linearly adsorbed CO species governed the performance of the Pt/MnO in the RWGS. [ABSTRACT FROM AUTHOR]

A series of CeO2 supported Cu, Co, and Ni catalysts have been synthesized by the wet-impregnation method for CO2 thermo-catalytic hydrogenation from 200 to 400 °C in the fixed bed reactor. All catalysts were characterized by XRD, N2-isotherms, and H2 temperature-programmed reduction. XRD results have suggested that the incorporated Cu, Co, and Ni have uniformly distributed on the CeO2 surface, N2-isotherm analysis confirmed that the pores of CeO2 were blocked by incorporated metals and H2-TPR indicated strong interaction between active metal and CeO2. The CO2 consumption rate and product selectivity depend on the type of active metal on CeO2 and reaction temperature. The order of CO2 consumption rate for 5 wt.% catalysts was 5Ni/CeO2 > 5Co/CeO2 > 5Cu/CeO2 at 400 °C. The high CO2 consumption rate for 5Ni/CeO2 was attributed to the presence of more number of active metallic Ni during the reaction which dissociated H2 molecule to H-atoms. The formed H-atoms reacted with active CO2 molecule and formed CH4 with 100% selectivity. [ABSTRACT FROM AUTHOR]