The dissociative chemisorption of small molecules such as methane and water on metal surfaces is a key step in many important catalyzed reactions. However, it has only very recently become possible to directly compare theory with molecular beam studies of these reactions. For most experimental conditions, such a comparison requires accurate methods for introducing the effects of lattice motion into quantum reactive scattering calculations. We examine these methods and their recent application to methane and water dissociative chemisorption. New results are presented for CO chemisorption and methane dissociation at step edges. The type of molecule-lattice coupling that leads to a strong variation in the dissociative sticking of methane with temperature is shown to occur for many polyatomic-metal systems. Improvements to these models are discussed. The ability to accurately compare theory with molecular beam experiments should lead to improved density functionals and consequently more accurate thermal rate constants for these important reactions.
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http://dx.doi.org/10.1021/acs.jpclett.6b01948 | DOI Listing |
Nanotechnology
December 2024
College of Physics and Energy, Qinghai Nationalities University, Xining 810007, People's Republic of China.
Two-dimensional MC-MXenes, characterized by their lightweight nature, tunable surface structures, and strong affinity for hydrogen, hold significant promise for addressing various challenges in hydrogen energy utilization. This study focuses on investigating the hydrogen adsorption and desorption properties, as well as the stability of hydrogenated compounds in 19 pure MC-MXenes nanosheets. The results indicate that hydrogen adsorption on MC primarily occurs through weak physisorption, with MnC and FeC from the fourth period, and AgC and CdC from the fifth period exhibiting the lowest adsorption energies.
View Article and Find Full Text PDFChem Sci
January 2025
Leiden Institute of Chemistry, Gorlaeus Laboratories P. O. Box 9502 2300 RA Leiden The Netherlands
The accurate modeling of dissociative chemisorption of molecules on metal surfaces presents an exciting scientific challenge to theorists, and is practically relevant to modeling heterogeneously catalyzed reactive processes in computational catalysis. The first important scientific challenge in the field is that accurate barriers for dissociative chemisorption are not yet available from first principles methods. For systems that are not prone to charge transfer (for which the difference between the work function of the surface and the electron affinity of the molecule is larger than 7 eV) this problem can be circumvented: chemically accurate barrier heights can be extracted with a semi-empirical version of density functional theory (DFT).
View Article and Find Full Text PDFOzone in the troposphere poses significant environmental and health risks, contributing to global warming and being linked to respiratory diseases, making it critical to find effective methods to remove ozone from the atmosphere. This study investigates the adsorption of ozone on boron nitride (BN) monolayers doped with metal-free elements, specifically carbon, silicon, oxygen, and phosphorus, using first-principles calculations based on Density Functional Theory (DFT). Our results showed that ozone adsorbed on boron nitride doped with carbon exhibited physisorption and had an adsorption energy of -0.
View Article and Find Full Text PDFJ Chem Phys
November 2024
Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
Yttria-stabilized zirconia (YSZ) is found in a wide range of applications, from solid-oxide fuel cells to medical devices and implants. A molecular-level understanding of the hydration of YSZ surfaces is essential for optimizing its performance and durability in these applications. Nevertheless, only a limited amount of literature is available about the surface hydration of YSZ single crystals.
View Article and Find Full Text PDFJ Am Chem Soc
November 2024
Institute of Molecular Science, Shanxi University, Taiyuan 030006, P. R. China.
CO as a typical σ-donor is one of the most important ligands in chemistry, while planar B is experimentally known as the most prominent magic-number boron cluster analogous to benzene. Joint gas-phase mass spectroscopy, collision-induced dissociation, and first-principles theory investigations performed herein indicate that B reacts with CO successively under ambient conditions to form a series of boron carbonyl complexes B(CO) up to = 7, presenting the largest boron carbonyl complexes observed to date with a quasi-planar B core at the center coordinated by CO ligands around it. Extensive theoretical analyses unveil both the chemisorption pathways and bonding patterns of these aromatic B(CO) monocations which, with three delocalized π bonds well-retained over the slightly wrinkled B moiety, all prove to be boron carbonyl analogs of benzene tentatively named as boron carbonyl aromatics (BCAs).
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