Dynamic behavior of molecular Pd-acetate trimers and dimers in heterogeneous vinyl acetate synthesis.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41354743.
- Also identified by DOI 10.1038/s41467-025-66820-7 and PMC identifier 12774893.
- Licence recorded as CC BY-NC-ND.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Vinyl acetate monomer (VAM) is a crucial intermediate in the production of various polymers. While molecular Pd-acetate trimers and dimers, such as Pd<sub>3</sub>(OAc)<sub>6</sub> and K<sub>2</sub>Pd<sub>2</sub>(OAc)<sub>6</sub>, are known to form on potassium acetate (KOAc)-promoted PdAu catalysts during heterogeneous VAM synthesis, their mechanistic role remains unclear. Here, we study the dynamics of different Pd-acetate species by utilizing in situ and operando crystallographic and spectroscopic characterizations combined with computational modeling on monometallic Pd model catalysts. The promoter-free catalyst expectedly shows low catalytic activity and VAM selectivity, corresponding to the complete reduction of Pd<sub>n</sub>(OAc)<sub>2n</sub> species to form Pd<sup>0</sup> and PdC<sub>x</sub> nanoparticles. Conversely, noticeable quantities of K<sub>n</sub>Pd<sub>2</sub>(OAc)<sub>n+4</sub> species remain on the KOAc-promoted catalyst, leading to smaller nanoparticle formation with 10 times the activity and double the selectivity for VAM. This study reveals that molecular Pd-acetate trimers and dimers are significant indicators of catalytic performance and highlights their structurally dynamic nature in heterogeneous vinyl acetate chemistry.