Tuning Surface Properties and Catalytic Performances of Pt–Ru Bimetallic Nanoparticles by Thermal Treatment

Abstract

The surface structure and catalytic properties of Pt–Ru bimetallic catalysts with identical bulk composition can be continuously tuned by treatment at different temperatures. The activity of these catalysts in CO oxidation was positively related to the treatment temperature, but the opposite trend was observed for the solvent‐free oxidation of benzyl alcohol. It was found that migration of Pt to the surface occurred when the treatment temperature was increased. During this process, the surface of the Pt–Ru nanoparticles changed from a Ru‐rich surface to a Pt‐rich surface. The electronic interactions between Pt and Ru became stronger with increased treatment temperature, and the amount of oxidized Pt species on the surface was higher for the samples treated at higher temperatures. Therefore, oxidized Pt species are more active in CO oxidation than other metallic species, but are less active in the selective oxidation of benzyl alcohol.

Selective Hydrogenation of ortho-Chloronitrobenzene over Biosynthesized Ruthenium–Platinum Bimetallic Nanocatalysts

“…However, higher calcination temperature might remove most of the residual plant biomass, which made the active species prone to agglomeration. On the other hand, the results was similar to that of the Pt–Ru/C reported by Zhang, who found that the activity decline predictably as increasing the treatment temperature. Higher treatment temperature could lead to more oxidized Pt species which was less active compared with the metallic Pt to provide hydrogen adsorption and dissociation site.…”

DFT Global Optimization of Gas-Phase Subnanometer Ru–Pt Clusters

“…In the literature, composition-induced structural changes , were shown for Pt–Ru nanoalloys and mixed structures were obtained at low temperatures. Nevertheless, a high-temperature treatment after synthesis − showed Pt segregation to the surface, leading to “core-shell” particles and it has been shown that core–shell Ru@Pt nanoalloys have higher catalytic activity for CO oxidation than mixed Ru–Pt nanoparticles …”

Constructing Pd/CeO2/C To Achieve High Leaching Resistance and Activity for Catalytic Wet Air Oxidation of Aqueous Amide

“…What is even worse is that, as indicated previously, the widely used metal oxide supports (i.e., ceria) always work as electron acceptors, making the complexation even easier. Our results indicated that the C support can give electrons to Pt and Cu metals to compensate the electron loss, , but carbon has no ability to activate and transfer oxygen to metal nanoparticles. Thus, what if we combine carbon and CeO 2 to take the advantage of both?…”

“…What is even worse is that, as indicated previously, the widely used metal oxide supports (i.e., ceria) always work as electron acceptors, making the complexation even easier. Our results indicated that the C support can give electrons to Pt and Cu metals to compensate the electron loss, 23,24 ■ RESULTS AND DISCUSSION Catalyst Preparation. The CeO 2 /C was prepared by the impregnation method with calcination (Supporting Information) to ensure the interaction between C and CeO 2 .…”

“…These results confirm electron transfer from Pd to the support. Carbon transfers electrons to noble metals 23 while oxides accept electrons from noble metals. 11 The obtained high electron density for Pd on carbon leads to its resistance to the lone pair electron of the N atom, which keeps the Pd metal from leaching.…”