Single-atom catalysis of CO oxidation using Pt1/FeOx

Abstract

Platinum-based heterogeneous catalysts are critical to many important commercial chemical processes, but their efficiency is extremely low on a per metal atom basis, because only the surface active-site atoms are used. Catalysts with single-atom dispersions are thus highly desirable to maximize atom efficiency, but making them is challenging. Here we report the synthesis of a single-atom catalyst that consists of only isolated single Pt atoms anchored to the surfaces of iron oxide nanocrystallites. This single-atom catalyst has extremely high atom efficiency and shows excellent stability and high activity for both CO oxidation and preferential oxidation of CO in H2. Density functional theory calculations show that the high catalytic activity correlates with the partially vacant 5d orbitals of the positively charged, high-valent Pt atoms, which help to reduce both the CO adsorption energy and the activation barriers for CO oxidation.

A non-syn-gas catalytic route to methanol production

“…Figure 5d,e shows further representative areas of the catalyst again with an unusually high density of ultra-small metal clusters composed of atom groups on the surface Pd/'Fe 2 O 3 ' . Zhang and co-workers have recently reported dispersed single Pt atoms on iron oxide using a similar preparative method as ours and they attributed the observed high activity for CO oxidation to the catalysis by these single metal sites 18 . Although we cannot discount the single metal site catalysis of this hydrogenolysis, more complex steric requirements for adsorption and catalysis of this substrate with metal sites are expected 19 .…”

Low-temperature carbon monoxide oxidation catalysed by regenerable atomically dispersed palladium on alumina

“…The stabilization of atomically dispersed transition metals such as Au, Pt and Rh on reducible oxides such as TiO 2 , FeO x and CeO 2 has been reported recently 2,3,20 . These catalysts have been shown to be active for reactions such as CO oxidation, water gas shift and also for olefin hydrogenation.…”

“…Similar results on single-atom catalysts were reported by for Pt on the reducible oxide FeO x (ref. 3). There is increasing interest in catalysis by single atoms, which promise high atom efficiency and improved low-temperature reactivity, as well as selectivity.…”

A highly active, stable and synergistic Pt nanoparticles/Mo2C nanotube catalyst for methanol electro-oxidation

“…Alternatively, increasing the activity per unit area and achieving a high dispersion of the active component could markedly increase the catalytic activity and decrease the necessary amount of the expensive component. 13,14 To this end, atomic layer deposition (ALD) is an attractive technique to deposit such thin films or nanosized catalysts because of its merits of simplicity, reproducibility and conformality. [15][16][17][18] Another effective strategy to improve the catalytic activity of the noble metal-based catalyst is using suitable catalyst promoter.…”