Bifunctionally faceted Pt/Ru nanoparticles for preferential oxidation of CO in H2

Global hydrogen production from catalytic reforming of hydrocarbons exceeds 50 million tons annually and accounts for 2-5% of global energy consumption. The hydrogen product generally contains 0.5-1 vol % of CO, which must be removed for certain industrial applications. Preferential oxidation (PROX) of CO is regarded as a promising and cost-effective method for hydrogen purification and potentially applicable to new generation fuel cell vehicles. In this work, bifunctionally faceted Pt/Ru nanoparticle catalysts are designed and fabricated via selective atomic layer deposition, which provides an unprecedented capability of tuning nanoparticles' structure-property relationship for PROX in H-2. Pt atomic layers are selectively deposited onto (001) facets of Ru, while leaving neighboring Ru surfaces exposed. By modulating the extent of electron donation with varied Pt coating configurations, it is demonstrated that the bifunctional catalyst with a single monolayer of Pt on Ru shows optimal activity and selectivity. The enhancement of PROX performance originates from the elimination of competitive CO adsorption on Pt, where a neighboring exposed Ru surface could readily provide highly active sites for O-2 dissociation. (C) 2021 Elsevier Inc. All rights reserved.

Automated summary

This paper designs bifunctional Pt/Ru nanoparticle catalysts via selective atomic layer deposition for PROX in H-2, showcasing optimal activity and selectivity. The enhancement in PROX performance is attributed to the elimination of competitive CO adsorption on Pt, allowing neighboring exposed Ru surfaces to provide highly active sites for O-2 dissociation.