Ag-Pt alloy nanoparticles with the compositions in the miscibility gap

Journal Article · Tue Jul 15 04:00:00 EDT 2008 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2008.03.013· OSTI ID:21128342

Zhenmeng, Peng ^[1]

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1. Department of Chemical Engineering, University of Rochester, Gavett Hall 206, Rochester, NY 14627-0166 (United States)

Silver platinum binary alloys with compositions between about Ag{sub 2}Pt{sub 98} and Ag{sub 95}Pt{sub 5} at <{approx} 400 deg. C have largely not been observed in bulk due to the large immiscibility between these two metals. We present in this paper that Ag-Pt alloy nanostructures can be made in a broad composition range. The formation of Ag-Pt nanostructures is studied by powder X-ray diffraction (PXRD) and energy-dispersive X-ray (EDX). Our results indicate that lattice parameter changes almost linearly with composition in these Ag-Pt nanomaterials. In another word, lattice parameter and composition relationship follows the Vegard's law, which is a strong indication for the formation of metal alloys. Our transmission electron microscopy (TEM) study shows that the silver-rich Ag-Pt alloy nanostructures have spherical shape, while the platinum-rich ones possess wire-like morphology. The stability and crystal phase are investigated by annealing the alloy nanostructures directly or on carbon supports. - Graphical abstract: While platinum and silver cannot form a solid solution with the composition between about Ag{sub 2}Pt{sub 98} and Ag{sub 95}Pt{sub 5} at 400 deg. C or below in bulk form, alloy particles and wires can be made within this miscibility gap at the nanometer scale.

• OSTI ID: 21128342
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 7 Vol. 181; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ANNEALING
BINARY ALLOY SYSTEMS
LATTICE PARAMETERS
MORPHOLOGY
NANOSTRUCTURES
PARTICLES
PLATINUM ALLOYS
POWDERS
SEGREGATION
SILVER ALLOYS
SOLID SOLUTIONS
SOLUBILITY
SPHERICAL CONFIGURATION
TEMPERATURE RANGE 0400-1000 K
TRANSMISSION ELECTRON MICROSCOPY
VEGARD LAW
X-RAY DIFFRACTION