Double-layered nanoparticle stacks for spectro-electrochemical applications.

Area of Science:

• Nanotechnology
• Materials Science
• Electrochemistry

Background:

• Spectro-electrochemical applications require surfaces with tunable optical properties and electrochemical activity.
• Existing nanostructures may not offer simultaneous enhancement at excitation and emission wavelengths.

Purpose of the Study:

• To present a novel double-layered nanoparticle stack surface for spectro-electrochemical applications.
• To demonstrate the tunable surface plasmon resonances and electrochemical applicability of the nanostructure.

Main Methods:

• Fabrication of a nanostructure using a gold layer and periodic arrays of gold and tantalum pentoxide nanodisks.
• Characterization using reflection spectroscopy in the visible wavelength region.
• Computational modeling using the finite-difference-time-domain method.
• Electrochemical evaluation via cyclic voltammetry.

Main Results:

• The nanostructure exhibited multiple surface plasmon (SP) resonances, confirmed by experimental spectra and simulations.
• The SP resonances were tunable to different wavelength regions.
• Cyclic voltammetry confirmed the nanostructure's suitability for electrochemical methods involving redox processes.

Conclusions:

• The presented nanoparticle surface is a promising platform for spectro-electrochemical applications.
• The tunable multiple SP resonances enable simultaneous enhancement at excitation and emission wavelengths.
• The surface demonstrates robust electrochemical activity for interfacial redox processes.