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Synthesis of Single-Crystalline Core-Shell Metal-Organic Frameworks
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Strain-Enhanced Metallic Intermixing in Shape-Controlled Multilayered Core-Shell Nanostructures: Toward Shaped
Benjamin P Williams1, Allison P Young1, Ilektra Andoni1
1Department of Chemistry, Merkert Chemistry Center, Boston College, 2609 Beacon Street, Chestnut Hill, MA, 02467, USA.
Angewandte Chemie (International Ed. in English)
|March 21, 2020
Summary
Researchers developed a platform to control nanoparticle surface composition. This allows tuning nanocatalyst properties by managing metal intermixing in shaped nanoparticles, advancing tailored nanomaterial design.
Area of Science:
- Nanomaterials Science
- Surface Chemistry
- Catalysis
Background:
- Controlling the surface composition of shaped bimetallic nanoparticles is key for tunable geometric and electronic properties in nanocatalysts.
- Developing methods to precisely tune this composition is crucial for advancing nanocatalyst design.
Purpose of the Study:
- To design a platform for studying the intermixing process in shaped nanoparticles.
- To achieve controlled surface composition tuning in multilayered palladium-nickel-platinum (Pd-Ni-Pt) core-shell nanocubes.
Main Methods:
- Utilized multilayered Pd-Ni-Pt core-shell nanocubes as precursors.
- Employed transmission electron microscopy (TEM) to monitor metal intermixing.
- Characterized surface structure evolution via electrochemical methanol oxidation.
- Performed density functional theory (DFT) calculations to understand mixing mechanisms.
Main Results:
- Successfully tuned the intermixing of nickel (Ni) and platinum (Pt) by adjusting layer thickness and number.
- Preserved the nanoparticle shape during the intermixing process under mild conditions.
- DFT calculations indicated that shorter diffusion lengths and strain in the layered structure enhance low-temperature mixing.
Conclusions:
- The developed platform enables controlled intermixing in shaped nanoparticles.
- Insights gained advance the realization of shape-controlled multimetallic nanoparticles for specific applications.
- This work provides a pathway for tailoring nanocatalyst properties through precise surface composition control.
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