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In this work,we describe two synthetic procedures for preparing palladium doped 25-atom nanoclusters (referred to as Pd1Au24(SR)18,where ― SR represents thiolate,R=C2H4Ph).Pure Pd1Au24(SC2H4Ph)18 nanoclusters are isolated by solvent extraction and size exclusion chromatography.Mass spectrometry and optical spectroscopy analyses demonstrate that the Pd1Au24(SC2H4Ph)18 nanocluster adopts the same core-shell structure as that of the homogold Au25(SC2H4Ph)18 nanocluster,that is,a Pd-or Au-centered icosahedron surrounded by six Au2(SR)3 “staple”-like motifs.Similar doping behavior has also been observed in 38-atom M38(SR)24 (M:metal) nanoclusters,indicating the unique behavior of Pd dopant being preferentially located in the icosahedral center.The catalytic activity of Pd1Au24(SC2H4Ph)18 has also been evaluated for the selective hydrogenation of α,β-unsaturated ketone (e.g.,benzalacetone) to α,β-unsaturated alcohol,and a 42% conversion of benzalacetone is attained.
In this work, we describe two synthetic procedures for preparing palladium doped 25-atom nanoclusters (referred to as Pd1Au24 (SR) 18, where - SR represents thiolate, R = C2H4Ph) Pure Pd1Au24 (SC2H4Ph) 18 nanoclusters are isolated by solvent extraction and size exclusion chromatography. Mass spectrometry and optical spectroscopy analyzes demonstrate that the Pd1Au24 (SC2H4Ph) 18 nanocluster adopts the same core-shell structure as that of the homogold Au25 (SC2H4Ph) 18 nanocluster, that is, a Pd-or Au-centered icosahedron surrounded by six Au2 (SR) 3 “staple” -like motifs. Similar doping behavior has also been observed in 38-atom M38 (SR) 24 (M: metal) nanoclusters, indicating the unique behavior of Pd dopant being preferentially located in the icosahedral center. The catalytic activity of Pd1Au24 (SC2H4Ph) 18 has also been derived for the selective hydrogenation of α, β-unsaturated ketone (eg, benzalacetone) to α, β-unsaturated alcohol, and a 42% conversion of benzalacetone is attained.