Black-CuO: surface-enhanced Raman scattering and infrared properties

Area of Science:

• Materials Science
• Nanotechnology
• Spectroscopy

Background:

• Surface-enhanced Raman scattering (SERS) requires substrates with high surface area and specific optical properties.
• Copper oxide (CuO) nanostructures offer potential as SERS substrates due to their tunable properties.

Purpose of the Study:

• To prepare nanotextured black CuO surfaces for SERS applications.
• To investigate the effect of gold (Au) film thickness on SERS performance.
• To explore the potential of these substrates for sensing and thermal applications.

Main Methods:

• Chemical etching of copper (Cu) to create nanotextured black CuO.
• Magnetron sputtering of nanoscale-conformal Au films onto CuO.
• Synchrotron X-ray photoelectron spectroscopy (XPS) for surface composition analysis.
• Infrared (IR) spectroscopy for reflectivity measurements.

Main Results:

• Nanotextured black CuO samples were successfully prepared.
• SERS intensity of thiophenol self-assembled monolayers (SAMs) increased with Au film thickness.
• A high SERS yield of approximately 10(4) counts/s/mW was achieved.
• XPS confirmed high purity CuO on the etched Cu surface.
• IR spectra showed a broad increase in reflectivity from 25% to 100%.

Conclusions:

• Nanotextured black CuO coated with Au films are effective SERS substrates.
• The Au film thickness is a critical parameter for optimizing SERS sensitivity.
• These substrates show promise for sensitive chemical detection and warrant further investigation for thermal effects in SERS.