Redox-mediated conversion of atomically dispersed platinum to sub-nanometer particles

Abstract

The concentration of Ce3+ centers in Pt–CeO2 films determines the onset of reduction of atomically dispersed platinum species.

Nanoscale architecture of ceria-based model catalysts: Pt–Co nanostructures on well-ordered CeO2(111) thin films

“…The authors [36] argued that formation of CoO becomes feasible due to the nanostructured nature of thin CeO2 films. Alternatively, the formation of Co 2+ species is also consistent with the formation of solid Co-CeO2 solution in a manner similar to the behavior observed for Sn-doped and Ga-doped CeO2 [38][39][40][41]. In fact, stable solid solution phases with a uniform dispersion of Co in the CeO2 lattice were observed in Co/CeO2 catalysts prepared by means of the sol-gel synthesis [42].…”

Tuning Pt-CeO2 interactions by high-temperature vapor-phase synthesis for improved reducibility of lattice oxygen

“…Previous theoretical studies on the reducibility of ceria-supported Pt catalysts showed that Pt 2+ species had an effect on the reducibility of ceria. Pt 2+ species can replace a Ce 4+ cation and adopt a square-planar coordination, creating an oxygen vacancy and leaving three three-coordinate oxygen atoms that are easier to remove 58 , 59 . However, even though in our work both catalysts have ionic Pt species in the as-synthesized state, the bonds between Pt and CeO 2 are different.…”

Pt/CeO2 and Pt/CeSnOx Catalysts for Low-Temperature CO Oxidation Prepared by Plasma-Arc Technique

“…Sn atoms were shown in a combined experimental and DFT study to easily reduce ceria nanoparticles, both bare and doped by Pt atoms acquiring the oxidation state +2 (Lykhach et al, 2017b ). First, only Ce 4+ cations were partially reduced upon interactions of atomic Sn with Pt/ceria nanoparticles, but already a moderate increase of Sn content resulted in the reduction of cationic Pt 2+ species to essentially neutral atomic ones prone to form Pt clusters.…”