Novel Powder-Supported Size-Selected Clusters for Heterogeneous Catalysis under Realistic Reaction Conditions

• Published in: Journal of physical chemistry. C 2012-12, Vol.116 (50), p.26295-26299
• Main Authors: Habibpour, V, Song, M. Y, Wang, Z. W, Cookson, J, Brown, C. M, Bishop, P. T, Palmer, R. E
• Format: Article
• Language: English
• Subjects: Catalysis; Catalysts: preparations and properties; Chemistry; Exact sciences and technology; General and physical chemistry; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp306263f

Well-defined nanoparticles show promise as model catalysts in the quest for new/improved practical catalysts with tunable chemical properties. Here we demonstrate the production, chemical performance, and stability of a new class of model catalyst systems, consisting of size-selected (PdN) nanoclusters supported on (graphite) powders suitable for realistic, test tube reaction conditions. The catalyst powders were synthesized by cluster beam deposition onto planar surface followed by microdicing. Cluster size-dependent (N = 55 to 400) catalytic activity/selectivity was observed in the vapor phase hydrogenation of 1-pentyne. Aberration-corrected scanning transmission electron microscopy of the nanocluster catalysts before and after catalytic measurements revealed the stability of the cluster catalysts against sintering. Larger nanoclusters, e.g., Pd400, showed superior activity, thermal stability, and (very high) selectivity over a period of hours in the reactor.