Low-cost SERS substrate featuring laser-ablated amorphous nanostructure

In this work, we aimed at fast and scalable manufacturing of low-cost SERS substrates using ultrashort-pulse laser-induced plasma-assisted ablation (LIPAA) of soda-lime glass. A two-step approach of amorphous nanostructure formation on the glass surface and subsequent deposition of 170 nm silver layer resulted in homogenous SERS-active substrates covered with nanostructures of around 100 nm in diameter, forming 1-3 mu m size dendrimers. The average enhancement factor (EF) evaluated using thiophenol was 3.0 x 105, while the surface activity was found to be consistent at any given point of substrates. Relatively modest EF was explained by amorphous, rounded-shaped features on soda-lime glass formed during the LIPAA-induced melting and subsequent solidification. That resulted in a lesser amount of hot spots but increased surface homogeneity. The use of soda-lime glass to fabricate SERS substrates promises a cheaper and scalable alternative to more widely used sapphire and other material substrates opening prospects for low-cost routine SERS testing with high reproducibility in chemistry, medical, forensic, and environmental sciences.

Automated summary

Using ultrashort-pulse laser-induced plasma-assisted ablation on soda-lime glass, researchers developed SERS substrates with amorphous nanostructures and a silver layer, resulting in homogeneous SERS activity with consistent surface activity. The relatively modest enhancement factor was attributed to the amorphous features on the glass, which led to fewer hot spots but increased surface homogeneity. The use of soda-lime glass offers a cheaper and scalable alternative for routine SERS testing in various scientific fields.