Low Temperature Physics: 32, 1097 (2006); https://doi.org/10.1063/1.2389021 (7 pages)
Физика Низких Температур: Том 32, Выпуск 11 (Ноябрь 2006), c. 1441-1448    ( к оглавлению , назад )

The polymerization of acetylene on supported metal clusters

S. Gilb, M. Arenz, and U. Heiz

Technische Universitüt München, Lehrstuhl für Physikalische Chemie Lichtenbergstr. 4, 85747 Garching, Germany
E-mail: ulrich.heiz@mytum.de

Received May 29, 2006, revised August 29, 2006

Аннотация

The polymerization of acetylene was studied by thermal programmed reaction on model catalysts consisting of size-selected Ag, Rh, and Pd atoms and Pdn (1 ≤ n ≤ 30) clusters on well-characterized MgO(111) thin films. In a single-pass heating cycle experiment, benzene, butadiene, and butane were catalyzed with different selectivities as function of cluster size: palladium and rhodium atoms selectively produce benzene, and the highest selectivity for butadiene is observed for Pd6, whereas Pd20 reveals the highest selectivity for butane. Ag atoms are inert. These results provide an atom-by-atom observation of the selectivity of small cluster catalysts.

PACS:
82.33.Hk - Reactions on clusters
82.65.+r - Surface and interface chemistry; heterogeneous catalysis at surfaces (for temporal and spatial patterns in surface reactions, see 82.40.Np; see also 82.45.Jn Surface structure, reactivity and catalysis in electrochemistry)
36.40.Jn - Reactivity of clusters

Ключевые слова: small clusters catalysts, cyclotrimerization reaction, Ag, Rh, and Pd atoms, dependent reactivity, polymerization selectivity.