Description |
Plasmonics, the study of light metal interactions, has shown great potential in the fields of spectroscopy, catalysis, medicine, and photovoltaics. There is significant interest in the design of metal nanoparticles that interact with specific wavelengths of light. By changing the size, shape, and metal composition, nanoparticles can be tuned to interact with different regions of the electromagnetic spectrum. Gold and silver are the two most common metals used in plasmonics, but are inefficient in the ultraviolet (UV) wavelength range and expensive. This has driven the research of plasmonics with non-noble metals that support plasmons in the UV and are cost-effective. Aluminum has been widely considered to be the ideal metal to fill this application has favorable plasmonic properties in the UV wavelength range and is cheap. However, Al is difficult to structure at the nanoscale due to its rapidly forming and chemically stable native oxide. Here we report the simple, large scale fabrication of Aluminum nanoparticle antennas. These nanoparticles have plasmon resonances in the UV, visible, near infrared, and infrared wavelengths. We demonstrate the utility of these nanoparticles as substrates for surface-enhanced infrared absorption spectroscopy, a wavelength range that is usually not associated with Aluminum. We also demonstrate that this fabrication technique allows for the fabrication of more complex nanoparticle geometries. These complex nanoparticles geometries have utility in both fundamental studies, and in surface-enhanced spectroscopies. We also demonstrate the potential of magnesium as a plasmonic metal. Magnesium is shown to support plasmon resonances from the UV to near infrared wavelengths. We investigate the plasmonic properties of nanostructured magnesium films and demonstrate that pure magnesium does not support sharp nanoscale features. By alloying magnesium with aluminum, its plasmonic and structural properties are improved. |