Hot-Carrier Generation in Bimetallic Janus Nanoparticles.

Area of Science:

• Nanotechnology
• Materials Science
• Physical Chemistry

Background:

• Localized surface plasmons in metallic nanoparticles generate energetic electrons and holes (hot carriers).
• These hot carriers are crucial for applications in photocatalysis, photovoltaics, and sensing.
• Bimetallic Janus nanoparticles offer unique properties for controlling hot carrier generation.

Purpose of the Study:

• To investigate hot carrier generation in bimetallic Janus nanoparticles (Au, Ag, Cu).
• To understand the influence of nanoparticle shape, composition, and light polarization on hot carrier generation.
• To provide insights for designing efficient hot-carrier devices.

Main Methods:

• Utilized an atomistic modeling approach combining macroscopic Maxwell equation solutions with quantum-mechanical tight-binding models.
• Analyzed spherical and dumbbell-shaped Janus nanoparticles.
• Studied the dependence on light polarization and nanoparticle geometry.

Main Results:

• The Ag-Au system showed the highest hot-carrier generation rate under solar illumination.
• Dumbbell-shaped nanoparticles exhibited increased hot carrier generation with larger neck sizes due to electric field enhancement.
• Maximum generation rates were achieved when the electric field was perpendicular to the metal interface.

Conclusions:

• Bimetallic Janus nanoparticles are promising for efficient hot carrier generation.
• Nanoparticle shape and light polarization significantly impact performance.
• This research guides the experimental design of advanced hot-carrier devices.