Bimetallic platinum-gold nanoparticles

Chalcogenides are commonly synthesized by this method. The metal sulphide syntheses have been carried out in ethanol, water, " and ethylenediamine, " whereas the sources of metal ions have been acetates or the chlorides. The precursor for sulfur is usually thioacetamide or thiourea. Nanoparticle synthesis of d-block elements have also been carried out, for example, platinum, gold, cobalt, iron, palladium, gold, nickel, and bimetallic alloys such as Co/Cu, 52i Pt/Ru, i Au/Pd, i Fe/Co. ... 

Other one-pot preparations of bimetallic nanoparticles include NOct4(BHEt3) reduction of platinum and ruthenium chlorides to provide Pto.sRuo.s nanoparticles by Bonnemann et al. [65-67] sonochemical reduction of gold and palladium ions to provide AuPd nanoparticles by Mizukoshi et al. [68,69] and NaBH4 reduction of dend-rimer—PtCl4 and -PtCl " complexes to provide dend-rimer-stabilized PdPt nanoparticles by Crooks et al. [70]. 

To determine the phase properties of the calcined bimetallic nanoparticles, a detailed x-ray diffraction (XRD) study was carried out. The XRD data of AuPt/C showed that the diffraction patterns for the carbon-supported nanoparticles show a series of broad Bragg peaks, a picture typical for materials of limited structural coherence. Nevertheless, the peaks are defined well enough to allow a definitive phase identification and structural characterization. The diffraction patterns of Au/C and Pt/C could be unambiguously indexed into an fcc-type cubic lattice occurring with bulk gold and platinum. We estimated the corresponding lattice parameters by carefully determining... 

J. Luo, M. M. Maye, V. Petkov, N. N. Kariuki, L. Wang, P. Njoki, D. Mott, Y. Lin, and C. J. Zhong, Phase properties of carbon-supported gold—platinum nanoparticles with different bimetallic compositions, Chem. Mater, in press... 

Bimetallic nanoparticles are of wide interest since they lead to many interesting size-dependent electrical, chemical, and optical properties [1]. They are particularly important in the field of catalysis since they often exhibit better catalytic properties than their monometallic counterparts [2-6]. Gold is very useful as an alloying metal and it has been used in conjunction with metals such as palladium [1,3,4,7-11] and platinum [6,10,11,20-24] for various catalytic reactions. The structure of bimetallic combinations depends mainly on the preparation conditions and the miscibility of the two components. Among the bimetallics, Au-Pd is one of the combinations that has been extensively studied in terms of preparation, stabilisation, and catalytic activity. Particularly, the use of preformed metallic sol as precursor of heterogeneous catalysts apparently shows the more tuneable method for preparing bimetallic particle. Turkevich and Kim have studied the morphology of Au-Pd bimetallic particles, prepared... 

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