Recyclable 3D Au NPs@ZnO Nanorods@Inverted Triangular Pyramid Cu as SERS Substrates for Pollutant Detection

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Surface-enhanced Raman scattering (SERS) is crucial for rapid food safety detection.
• Existing noble metal/ZnO SERS substrates are often limited to flat surfaces.
• Research on micro/nanostructured ZnO for self-cleaning, high-sensitivity SERS is limited.

Purpose of the Study:

• To develop a novel self-cleaning composite SERS substrate using micro/nanostructured surfaces.
• To investigate the fabrication of Au NPs@ZnO NRs (NSs)@ITP Cu.
• To evaluate the SERS performance and self-cleaning properties of the fabricated substrate.

Main Methods:

• Fabrication via nanoindentation, hydrothermal synthesis, and magnetron sputtering.
• Investigated the influence of machining and hydrothermal parameters on ZnO morphology.
• Characterized SERS performance using R6G and MG detection and UV-visible irradiation for degradation.

Main Results:

• Optimized inverted triangular pyramid (ITP) structures enabled vertically aligned ZnO nanorod growth.
• Achieved 50.8x and 33.5x higher electric field intensities for Au NPs@ZnO NRs@ITP Cu and Au NPs@ZnO NSs@ITP Cu, respectively.
• Demonstrated ultrasensitive detection of R6G (10⁻⁹ mol/L) and MG (10⁻⁷ mol/L) with rapid degradation under UV-visible light.

Conclusions:

• The developed Au NPs@ZnO NRs@ITP Cu substrate exhibits excellent SERS performance and self-cleaning capabilities.
• This recyclable, ultrasensitive SERS substrate shows significant potential for pollutant detection.
• Tailoring nanostructure morphology is key to enhancing SERS substrate efficiency.