Reactive tunnel junctions in electrically driven plasmonic nanorod metamaterials.

Area of Science:

• Materials Science
• Chemistry
• Physics

Background:

• Non-equilibrium hot carriers at interfaces are vital for catalysis and optoelectronics.
• Hot carriers can be efficiently generated via electron tunneling excitation.

Purpose of the Study:

• To demonstrate that hot electron generation in nanoscale tunnel junctions enhances reactivity.
• To show that these reactions can modulate the tunneling process itself.
• To develop an electrically driven platform for studying these phenomena.

Main Methods:

• Fabrication of a device with an array of electrically driven plasmonic nanorods.
• Achieving high density of nanoscale tunnel junctions (up to 10^11 cm^-2).
• Utilizing hot-electron activation for oxidation (O2) and reduction (H2) reactions.
• Monitoring reaction kinetics via radiative decay of tunneling-induced surface plasmons.

Main Results:

• Nanoscale tunnel junctions exhibit high reactivity due to hot electron generation.
• Electrically driven nanorods facilitate confined oxidation and reduction reactions.
• Reaction kinetics are monitored in situ using plasmon decay.
• Demonstrated modulation of tunneling by induced chemical reactions.

Conclusions:

• Electrically driven plasmonic nanorods create a powerful platform for nanoscale chemical reactions.
• This approach enables the development of advanced chemical and optoelectronic devices.
• Hot electron tunneling is a viable mechanism for driving and controlling nanoscale chemical processes.