Altering CO binding on gold cluster cations by Pd-doping

Abdulhussein, Heider A.; Ferrari, Piero; Vanbuel, Jan; Heard, Christopher J.; Fielicke, André; Lievens, Peter; Janssens, Ewald; Johnston, Roy L.

doi:10.1039/c9nr04237g

Cited by 23 publications

(18 citation statements)

References 98 publications

(123 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the Supporting information, we estimate CO binding energies using the measured dissociation rates, employing RRKM theory that directly uses the calculated vibrational modes of the complexes to account for possible changes in heat capacity upon doping. A similar analysis has been performed for related systems [27,57,58] . The analysis confirms that the increased k d induced by doping correlates with a reduced CO binding energy and thus a weakening of the Pt‐CO interaction induced by germanium.…”

Section: Resultssupporting

confidence: 68%

“…LC‐ωPBEh was chosen in order to treat long‐range charge transfer effects due to the difference in electronegativity between Pt and the dopant. This DFT functional has been used previously with great success for investigating Ag, Au and Pd nanoclusters [57,78,79] . Vibrational frequencies were calculated to ensure that the structures were true minima on the PES and to calculate the zero‐point energy (ZPE) corrections.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Doping Platinum with Germanium: An Effective Way to Mitigate the CO Poisoning

et al. 2021

Self Cite

View full text Add to dashboard Cite

The vulnerability towards CO poisoning is a major drawback affecting the efficiency and long‐term performance of platinum catalysts in fuel cells. In the present work, by a combination of density functional theory calculations and mass spectrometry experiments, we test and explain the promotional effect of Ge on Pt catalysts with higher resistance to deactivation via CO poisoning. A thorough exploration of the configurational space of gas‐phase Ptn+ and GePtn−1+ (n=5–9) clusters using global minima search techniques and the subsequent electronic structure analysis reveals that germanium doping reduces the binding strength between Pt and CO by hindering the 2π‐back‐donation. Importantly, the clusters remain catalytically active towards H2 dissociation. The ability of Ge to weaken the Pt−CO interaction was confirmed by mass spectrometry experiments. Ge can be a promising alloying agent to tune the selectivity and improve the durability of Pt particles, thus opening the way to novel catalytic alternatives for fuel cells.

show abstract

Section: Resultssupporting

confidence: 68%

Section: Methodsmentioning

confidence: 99%

Doping Platinum with Germanium: An Effective Way to Mitigate the CO Poisoning

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…As a bulk material, gold is the noblest of all metals [ 1 ]. At the nanoscale, however, gold becomes reactive towards several molecules, and can selectively catalyze certain reactions, which has attracted broad scientific attention [ 2 , 3 , 4 , 5 ]. Intriguingly, gold cationic clusters are also reactive towards noble gas atoms [ 6 ].…”

Section: Introductionmentioning

confidence: 99%

Argon Adsorption on Cationic Gold Clusters Aun+ (n ≤ 20)

Ferrari¹,

Janssens²

2021

Molecules

Self Cite

View full text Add to dashboard Cite

The interaction of Aun+ (n ≤ 20) clusters with Ar is investigated by combining mass spectrometric experiments and density functional theory calculations. We show that the inert Ar atom forms relatively strong bonds with Aun+. The strength of the bond strongly varies with the cluster size and is governed by a fine interplay between geometry and electronic structure. The chemical bond between Aun+ and Ar involves electron transfer from Ar to Au, and a stronger interaction is found when the Au adsorption site has a higher positive partial charge, which depends on the cluster geometry. Au15+ is a peculiar cluster size, which stands out for its much stronger interaction with Ar than its neighbors, signaled by a higher abundance in mass spectra and a larger Ar adsorption energy. This is shown to be a consequence of a low-coordinated Au adsorption site in Au15+, which possesses a large positive partial charge.

show abstract

“…This change in the stability pattern with size is attributed to Au always delocalizing its 6s electron in PdAu n-1 + , whereas Pd can delocalize a 4d-electron depending on cluster size and cluster structure. Pd doping can also affect the cluster reactivity, illustrated by the increased CO and O 2 binding energies on the doped clusters, compared to bare Au n + [32,33]. For CO adsorption, the increase in binding energy becomes more pronounced from n = 7, as determined by a combination of mass spectrometry and statistical modelling [32].…”

Section: Introductionmentioning

confidence: 99%

“…Pd doping can also affect the cluster reactivity, illustrated by the increased CO and O 2 binding energies on the doped clusters, compared to bare Au n + [32,33]. For CO adsorption, the increase in binding energy becomes more pronounced from n = 7, as determined by a combination of mass spectrometry and statistical modelling [32]. Furthermore, Pd doping was shown to quench optical absorption cross sections in the visible range [34,35].…”

Section: Introductionmentioning

confidence: 99%