Inorganic Chemistry, Vol.48, No.13, 6152-6158, 2009
Bismuth-Palladium Heterometallic Carboxylate as a Single-Source Precursor for the Carbon-Supported Pd-Bi/C Catalysts
The heterometallic complex i(2)Pd(2) O2CC (3) (10) O2CC (3) (2) 1) was obtained by the solid state reaction of Bi-III trifluoroacetate trifluoroacetic acid adduct with unsolvated trinuclear Pd-II trifluoroacetate. he crystal structure of 1 consists of discrete tetranuclear molecules, in which two paddlewheel [BiPd(O2CC (3) (4) units are connected by two chelating bridging trifluoroacetate ligands through bismuth ends. here are no metal-metal bonds in the tetrameric structure of 1, since both Bi center dot center dot center dot Pd (3,0843(4) A and i center dot center dot center dot Bi (4.5074(4) A distances am too king to be considered as bonding interactions. A study of (he solution behavior revealed that not only die coordinated trifluoacetic acid in 1 can be effectively replaced by other donor solvent molecules but also the tetranuclear complex can be cleaved in solution into discrete dinuclear i-Pd species. Complex 1 was used as precursor for the preparation of a bimetallic Pd-Bi carbon supported catalyst. lie preparation procedure included the modification of the carbon support to increase the number of oxygenated function at its surface followed by grafting complex 1 via ligand exchange for surface carboxylates and activating the thermally.. he resulting catalyst consisting of small supported metallic particles was found to be more active than the reference materials prepared from multisource homometallic Pd and i precursors.