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Updated: Aug 28, 2025
Synthesis and Testing of Supported Pt-Cu Solid Solution Nanoparticle Catalysts for Propane Dehydrogenation
Published on: July 18, 2017
Substitutional-interstitial structural transition in Cu-Pt nano-alloys
Luke D Geoffrion1, Miguel José-Yacaman2, Alexander Lehr2
1Department of Physics & Astronomy, University of Arkansas at Little Rock 2801 South University Avenue Little Rock AR 72204 USA gxguisbiers@ualr.edu.
Abstract:
Copper-platinum alloys are important binary alloys in catalysis. In this communication, we demonstrate that it is possible to preserve the thermal properties of platinum with a copper-platinum alloy by converting the substitutional alloy into an interstitial one. This conversion occurs when the size of the copper-platinum system is reduced down to the nanoscale. The size-dependent phase diagram of Cu-Pt for a spherical nanoparticle is calculated at various sizes (50, 10 and 5 nm) demonstrating that Cu-Pt alloyed nanoparticles can be formed all over the composition range. Experimentally, the electron microscopy characterization of copper-platinum alloyed nanoparticles synthesized by wet chemistry supports the predicted structural transition.
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