Enhanced catalytic CO oxidation by Cu13-mNim (m = 0, 1, 13) clusters at ambient temperatures with more active sites and distinct mechanistic pathways

The 2D or 3D morphology of sub-nanometer Cu5 and Cu8 clusters changes the mechanism of CO oxidation

“…This deformation into 3D morphology was also observed in our first study 28 and explains the resulting similarity between Cu 6 and 3D Cu 5 , Cu 7 and Cu 8 in the first part of the catalytic CO oxidation cycle. Given that O 2 dissociation is increasingly favoured with increasing size, it is coherent that larger particles also favour the initial O 2 dissociation over the LH bimolecular reaction with CO. 32–35 This is consistent with our previous statement that morphology brings the more significant changes and the results on Cu 5–8 clusters show that the differential reactivity is rapidly lost with increasing size as soon as the h -111 and h -100 facets become available. Indeed, the available reports on larger particles show that the second part of the cycle occurs via a LH mechanism in which the rate determining step is the O + CO reaction, which means that the whole reaction for Cu 8 is already qualitatively equivalent to that of larger clusters, namely, Cu 13 , 32 Cu 20 33 and Cu 55 .…”

“…Since the key feature behind the different behaviour of the smallest Cu n clusters was traced to their morphology, both the planar and the 3D isomers of Cu 5 are considered, together with a larger 3D Cu 8 cluster to clarify the effect of both cluster size and shape on this reaction. The present study completes the description of CO oxidation on small Cu n clusters, including the work by Wang et al 31 on Cu 6 and Cu 7 , and other studies featuring icosahedral Cu 13 , 32 Cu 20 33 and Cu 55 . 34,35…”

Highly Efficient Dehydrogenation of 2,3-Butanediol Induced by Metal–Support Interface over Cu-SiO2 Catalysts

“…On the basis of the lattice size, a 3 × 3 × 2 Monkhorst–Pack k -point grid was used to sample in the surface Brillouin zone. The small Cu nanoparticle was modeled by a Cu 13 cluster with a stable icosahedron structure, which has been applied in the catalysis simulation of various reactions as a realistic model for the Cu active sites. − The shell atoms of a Cu 13 cluster with a core–shell structure possess the same coordination number (Figure S3b). Currently, it is still challenging to identify the structure of the metal–support interface because of the various and indistinct structure properties of the interface.…”

Green Fabrication of Integrated Au/CuO/Oyster Shell Nanocatalysts with Oyster Shells as Alternative Supports for CO Oxidation

“…Likewise, from Figure e, we can know that the overlap of 4d states of Au and 3d, 4s states of Cu and 2p states of O is about −5.3 eV below the Fermi level. This phenomenon demonstrates the synergistic effect of CuO and Au NPs present in the CO chemisorption process. , …”

“…This phenomenon demonstrates the synergistic effect of CuO and Au NPs present in the CO chemisorption process. 52,53 4. CONCLUSIONS In this work, we have successfully synthesized an integrated Au/CuO/OS nanocatalyst by using natural OSs as support under a mild, universal, and less toxic manner, which exhibited good catalytic properties in gas-phase CO oxidation reaction.…”