Decoration of plasmonic Mg nanoparticles by partial galvanic replacement

Area of Science:

• Materials Science
• Nanotechnology
• Physical Chemistry

Background:

• Plasmonic nanostructures are crucial for light-matter interactions and chemical reactions.
• Recent advances utilize plasmonic materials with catalytic metals for enhanced reactivity.

Purpose of the Study:

• To demonstrate galvanic replacement on earth-abundant magnesium nanoparticles in a nonaqueous solvent.
• To create novel bimetallic and multimetallic architectures with tunable plasmonic properties.

Main Methods:

• Galvanic replacement reaction in a nonaqueous solvent.
• Electron-beam imaging and energy-dispersive X-ray spectroscopy for local composition mapping.
• Inductively coupled plasma mass spectrometry for ensemble analysis.
• High-resolution scanning transmission electron microscopy for interface characterization.
• Ultraviolet-visible spectrometry and darkfield scattering for optical property analysis.

Main Results:

• Successfully produced decorated magnesium nanoparticles with gold, silver, palladium, or iron.
• Characterized bimetallic architectures featuring a magnesium oxide separation layer.
• Observed strong plasmonic optical signals dependent on metallic decoration composition.
• Demonstrated potential for stepwise decoration with multiple metal compositions on a single particle.

Conclusions:

• Developed a novel method for creating magnesium-based bimetallic and multimetallic plasmonic nanostructures.
• These structures exhibit significant plasmonic optical signals.
• The novel designs offer potential for advanced applications in sensing and plasmon-assisted catalysis.