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Density functional theory (DFT) calculations are carried out to investigate the effect of point defects on acetylene hydrogenation reaction over Ni(111) surface with three different defect concentrations (DC = 0.0500, 0.0625, and 0.0833), compared with the perfect Ni(111) surface. The adsorptions of C species and H atoms and the mechanism of acetylene hydrogenation the ethylene pathway are systematically analyzed. The results indicate that the existence of defects will make C species and H atoms more inclined to adsorb near the defects. Introducing an appropriate amount of point defect concentration can enhance the catalytic activity and ethylene selectivity of Ni. In this work, DC = 0.0625 Ni(111) surface has the highest catalytic activity and selectivity of ethylene. This work provides useful theoretical information on the effect of defects on acetylene hydrogenation and is helpful for the design of Ni and related metal catalysts with defects.
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http://dx.doi.org/10.1039/d1cp03599a | DOI Listing |
Angew Chem Int Ed Engl
September 2025
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
The electrocatalytic acetylene semi-hydrogenation (EASH) driven by renewable energy offers an important non-petroleum route for ethylene production, yet suffers from insufficient reaction rate, ethylene selectivity, and energy efficiency. While tailoring catalytically active structures is effective for improving the EASH performance, the effects of mass transport at the mesoscale are poorly understood. Here, we show quantitatively the crucial role of interparticle mass transport within the catalyst layer of a gas diffusion electrode.
View Article and Find Full Text PDFChem Sci
August 2025
South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology Guangzhou 510640 China
Cyclic oligomers with multiple redox centers are ideal models for intramolecular electron transfer processes, as they feature well-defined spatial geometries and degenerate energy states. The design and synthesis of such structures with strongly interacting monomers, however, remains a significant challenge. Here, we report a one-pot synthesis of an acetylene-bridged ferrocene macrocycle (9) using alkyne metathesis, with a remarkable 43% isolated yield.
View Article and Find Full Text PDFACS Earth Space Chem
August 2025
Centre de Recherche sur les Ions, les Matériaux et la Photonique Normandie University, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, Caen 14000, France.
Studying the physicochemical properties of ice in astronomical environments is crucial to understanding the chemical processes involved in cosmic events such as comet and planet formation. The physical characteristics and chemical evolution on the surfaces of cosmic objects such as comets or interstellar grains offer key insights into these processes. This study focuses on α-pinene, a carbon- and hydrogen-rich molecule, which serves as a model for investigating radical-driven synthesis of more complex molecules under space-like conditions.
View Article and Find Full Text PDFTransition-metal-catalyzed C-H alkylation of heteroaromatics with alkenes represents an atom-economical and cost-effective strategy for accessing industrially and pharmaceutically relevant compounds. However, the selective C5-H alkylation of biomass-derived furfural and its isosteric analog, thiophene-2-carboxaldehyde, highly challenging yet industrially vital substrates, has remained elusive. Herein, we disclose a Ni/NHC-catalyzed strategy for the C5-H alkylation of furan- and thiophene-2-carboxaldehydes with styrenes and norbornene, enabled by a readily installable and recyclable N-PMP (p-methoxyphenyl) imine protecting group.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
August 2025
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, P.R. China.
The selective hydrogenation of acetylene to ethylene is a critical industrial process for purifying ethylene feedstocks. Palladium single-atom catalysts (Pd SACs) exhibit exceptional ethylene selectivity in this hydrogenation reaction. However, their isolated active sites show limited ability to capture and adsorb trace acetylene molecules from ethylene-rich streams, resulting in relatively low hydrogenation activity.
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