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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.
Copper-platinum alloy nanoparticles exhibit preserved thermal properties by transitioning to an interstitial structure at the nanoscale. This structural change enables tunable alloy compositions for catalytic applications.
Area of Science:
- Materials Science
- Nanotechnology
- Catalysis
Background:
- Copper-platinum (Cu-Pt) alloys are crucial in catalysis.
- Maintaining platinum's thermal properties in alloys is a significant challenge.
Purpose of the Study:
- To investigate the structural transformation of Cu-Pt alloys at the nanoscale.
- To demonstrate the preservation of thermal properties in nano-sized Cu-Pt alloys.
- To explore the composition range of Cu-Pt alloyed nanoparticles.
Main Methods:
- Calculation of the size-dependent phase diagram for spherical Cu-Pt nanoparticles.
- Synthesis of Cu-Pt alloyed nanoparticles using wet chemistry.
- Characterization of synthesized nanoparticles via electron microscopy.
Main Results:
- A structural transition from substitutional to interstitial alloy occurs in Cu-Pt systems at the nanoscale.
- Cu-Pt alloyed nanoparticles can be formed across the entire composition range.
- Experimental results confirm the predicted structural transition.
Conclusions:
- Nanoscale engineering enables the preservation of platinum's thermal properties in Cu-Pt alloys.
- The interstitial structure in nano-Cu-Pt alloys offers new possibilities for catalytic applications.
- Size-dependent phase diagrams are essential for designing nanomaterials with desired properties.
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