Herein, we report on the synthesis of ultrasmall Pd nanoclusters (∼2 nm) protected by L‐cysteine [HOCOCH(NH2)CH2SH] ligands (Pdn(L‐Cys)m) and supported on the surfaces of CeO2, TiO2, Fe3O4, and ZnO nanoparticles for CO catalytic oxidation. The Pdn(L‐Cys)mnanoclusters supported on the reducible metal oxides CeO2, TiO2and Fe3O4exhibit a remarkable catalytic activity towards CO oxidation, significantly higher than the reported Pd nanoparticle catalysts. The high catalytic activity of the ligand‐protected clusters Pdn(L‐Cys)mis observed on the three reducible oxides where 100 % CO conversion occurs at 93–110 °C. The high activity is attributed to the ligand‐protected Pd nanoclusters where the L‐cysteine ligands aid in achieving monodispersity of the Pd clusters by limiting the cluster size to the active sub‐2‐nm region and decreasing the tendency of the clusters for agglomeration. In the case of the ceria support, a complete removal of the L‐cysteine ligands results in connected agglomerated Pd clusters which are less reactive than the ligand‐protected clusters. However, for the TiO2and Fe3O4supports, complete removal of the ligands from the Pdn(L‐Cys)mclusters leads to a slight decrease in activity where the T100%CO conversion occurs at 99 °C and 107 °C, respectively. The high porosity of the TiO2and Fe3O4supports appears to aid in efficient encapsulation of the bare Pdnnanoclusters within the mesoporous pores of the support.
This content will become publicly available on November 30, 2024
Converting CO2to value‐added chemicals,
- NSF-PAR ID:
- 10481121
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemCatChem
- Volume:
- 16
- Issue:
- 3
- ISSN:
- 1867-3880
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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