Reusable and long-life 3D Ag nanoparticles coated Si nanowire array as sensitive SERS substrate

Surface enhanced Raman spectroscopy (SERS) has been developed as a powerful analytical tool in the fields of bio-medical engineering, environmental monitoring and so on. Using confocal Raman spectrometer, the SERS substrate can be used for spatial analysis. However, reusable and long-life SERS substrate is urgently needed since the low usage cost is critical to SERS sensor. In this manuscript, we introduced a 3D Ag nanoparticles coated Si nanowire array SERS substrate fabricated by simple nanofabrication. The enhancement factor of 3D Ag nanoparticles coated Si nanowires array SERS substrate was about 1 × 10⁶ and its relative standard deviation is 9.85%. The substrate can be used for more than ten times and the lifetime was longer than seventy days.