Monolayer protected Au nanocluster catalysts are known to undergo structural changes during catalytic reactions, including dissociation and migration of ligands onto the support, which strongly affects their activity and stability. To better understand how the nature of ligands influences the catalytic activity of such catalysts, three types of ceria supported Au nanoclusters with different kinds of ligands (thiolates, phosphines and a mixture thereof) have been studied, employing CO oxidation as model reaction. The thiolate-protected Au/CeO showed significantly higher CO conversion after activation at 250 °C than the cluster catalysts possessing phosphine ligands. Temperature programmed oxidation and infrared spectroscopy revealed that while the phosphine ligands seemed to decompose and free Au surface was exposed, temperatures higher than 250 °C are required to efficiently remove them from the whole catalyst system. Moreover, the presence of residues on the support seemed to have much greater influence on the reactivity than the gold particle size.
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http://dx.doi.org/10.1002/cctc.202200322 | DOI Listing |
Inorg Chem
January 2025
State Key Laboratory of Clean and Efficient Coal Utilization, Taiyuan University of Technology, Taiyuan 030024, China.
The low sulfur selectivity of Fe-based HS-selective catalytic oxidation catalysts is still a problem, especially at a high O content. This is alleviated here through anchoring FeO nanoclusters on UiO-66 via the formation of Fe-O-Zr bonds. The introduced FeO species exist in the form of Fe and Fe.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
CNRS/UCSD, Chemistry, University of California, San Diego, 5213 Pacific Hall,, Department of Chemistry, 92093-0343, La jolla, UNITED STATES.
N-Heterocyclic carbene (NHC) ligands possess the ability to stabilize metal-based nanomaterials for a broad range of applications. With respect to metal-hydride nanomaterials, however, carbenes are rare, which is surprising if one considers the importance of metal-hydride bonds across the chemical sciences. In this study, we introduce a bottom-up approach leveraging preexisting metal-metal m-center-n-electron (mc-ne) bonds to access a highly stable cyclic(alkyl)amino carbene (CAAC) copper-hydride nanocluster, [(CAAC)6Cu14H12][OTf]2 with superior stability compared to Stryker's reagent, a popular commercial phosphine-based copper hydride catalyst.
View Article and Find Full Text PDFRSC Adv
January 2025
Laboratory of Clean Low-Carbon Energy, Department of Thermal Science and Energy Engineering, University of Science and Technology of China Hefei 230023 PR China.
Crafting highly dispersed active metal sites on catalysts is an optimal method for improving the catalytic reactivity and stability, as it would improve atomic utilization efficiency, enhance reactant adsorption and activation ability through unique geometric and electronic properties. In this study, two synthesis methods were employed (ammonia evaporation (AE) and the impregnation method (IM)) to load Rh species onto the ZSM-5 support in order to attain tunable dispersivity, during which a 1.25-fold increase in the total yield of liquid oxygenated products (32 433.
View Article and Find Full Text PDFNanoscale
January 2025
School of Chemistry & Chemical Engineering, School of Materials Science and Engineering and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, Department of Chemistry and Center for Atomic Engineering of Materials, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of the Ministry of Education, Anhui University, Hefei, 230601, China.
Atomically precise nanoclusters (NCs) can serve as an excellent platform for a comprehensive understanding of structure-property relationships. Herein, three structurally similar Cu NCs (Cu-1, Cu-2 and Cu-3) have been prepared for the photocatalytic phenylacetylene self-coupling reaction. It was found that Cu-1 NC achieved the highest turnover number (TON) of 524.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Chemistry, Federal University of Paraná, Curitiba, 81531-980, Brazil.
Gold-based (Au) nanostructures are efficient catalysts for CO oxidation, hydrogen evolution (HER), and oxygen evolution (OER) reactions, but stabilizing them on graphene (Gr) is challenging due to weak affinity from delocalized [Formula: see text] carbon orbitals. This study investigates forming metal alloys to enhance stability and catalytic performance of Au-based nanocatalysts. Using ab initio density functional theory, we characterize [Formula: see text] sub-nanoclusters (M = Ni, Pd, Pt, Cu, and Ag) with atomicities [Formula: see text], both in gas-phase and supported on Gr.
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