Metal Clusters Dispersed on Oxide Supports: Preparation Methods and Metal-Support Interactions

Electronic Metal–Support Interactions between Pt Nanoparticles and Co(OH)2 Flakes for CO Oxidation

“…The additional CO adsorption band at 2063 cm –1 could only arise from the interaction between Pt nanoparticles and Co­(OH) 2 as Co­(OH) 2 does not adsorb CO under the experimental conditions as we have tested. It is well-known that CO adsorption on negatively charged noble metal (Au and Pt) surface atoms could shift the stretching frequencies to the red side by a large amount. ,,,,,,− The physical reason is that more negatively charged noble metals allow more electron back-donation to the CO 2π* orbitals, thus weakening the C–O bond strength in the CO molecule and red-shifting the CO stretching frequency. For example, Zhu et al reported negatively charged Pt δ− nanoparticles assembled on vacancy-abundant hexagonal boron nitride nanosheets (h-BNNS) because of the interfacial charge transfer from h-BNNS with vacancies to Pt.…”

“…Metal–support interactions play a key role in the catalytic performance of supported metal catalysts. − Very recently, a new type of metal–support interactions, the electronic metal–support interactions (EMSIs), has attracted increasing attention ever since it was first coined by Campbell in 2012 to understand the excellent activity of Pt/CeO 2 catalysts for dissociating the O–H bonds in water . In contrast to the classical strong metal–support interaction (SMSI), − the encapsulation of the metal by an overlayer of the support does not occur in the EMSI phenomenon, such that the active sites are still exposed to adsorbates.…”

Tunable Electronic Metal–Support Interactions on Ceria-Supported Noble-Metal Nanocatalysts in Controlling the Low-Temperature CO Oxidation Activity

“…CO oxidation reaction (CO + O 2 → CO 2 ) is an important benchmark reaction for both fundamental researches and practical applications. On the one hand, it has a close correlation with applications like automobile tail gas purification, CO sensor, and indoor air cleaning. − On the other hand, it is often used as model reactions to investigate the structure–activity relationship of the synthesized heterogeneous catalysts because of the simple catalytic mechanism. ,, The Mars van Krevelen (MvK) mechanism is most accepted by researchers, while other pathways containing some important intermediates are also reported. − CeO 2 -supported noble-metal nanomaterials are superior catalysts for many reactions not only because of the high activity and stability of noble metals but also because of the specific redox ability of CeO 2 . − Using CO oxidation reaction as a model reaction can help one to figure out the structure–function correlation of CeO 2 -supported noble-metal catalysts and thus benefit the design of the catalysts with the most proper structure for improving the activity and lowering the cost. Pt catalysts for CO oxidation are studied most among the noble metals.…”

Synthesis of Quasi‐Bilayer Subnano Metal‐Oxide Interfacial Cluster Catalysts for Advanced Catalysis

“…[ 2 ] In general, metal clusters tend to form a 3D shape to minimize their surface energies. [ 3 ] When metal‐support interactions are stronger than metal‐metal interactions, the metal clusters might change to a 2D raft, [ 4 ] which in turn brings about new electronic properties and further improves the metal utilization, thus boosting exceptional catalytic behaviors, sharply different from their counterparts of 3D clusters and nanoparticles (NPs). [ 5 ] For example, Au bilayer clusters on titania and iron oxide were found to be significantly more active than the monolayer and 3D ones by more than an order of magnitude in CO oxidation.…”