In this work, we aimed at investigating how good or bad aluminum (Al) and copper (Cu) perform in plasmonic applications as compared to silver (Ag) and gold (Au). Contrary to our expectations, and to widely accepted misconceptions, our experimental and simulation results show that Cu and Al layers on nanospheres make efficient nanostructures for surface-enhanced Raman spectroscopy. In an unprecedented one-to-one comparison among all metal nanostructures, it is demonstrated that Al and Cu rival the conventionally used materials, Ag and Au, displaying similar enhancement. The enhancement capability was shown with the metal nanostructures exposed to air under room conditions showing that the oxide layers formed on Al and Cu do not affect their SERS performance significantly. This concise report further supports large-scale chemical sensing applications using low-cost metals compatible with mass-production fabrication in microelectronics as well as demonstrating an appropriate way to compare the electric field enhancement of different plasmonic materials.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Electrical and Electronic Engineering
- Materials Chemistry