Bimetallic Au–Ag nanochains as SERS substrates

•Synthesis of Au–Ag bimetallic nanoparticles by pulsed laser ablation in water.•Au–Ag nanochains exhibit monotonic plasmon band.•Investigated plasmon hybridization by reducing the volume of the colloidal suspension by evaporation.•Au–Ag nanochains show SERS enhancement when tested with crystal violet probe molecules.

Au–Ag bimetallic nanochains were prepared using pulsed laser ablation in liquid medium. Synthesis was performed by ablating silver target in a gold colloidal suspension. The plasmon characteristics of the nanostructures are found to be sensitive to ablation duration. AFM and TEM images indicate that almost all nanoparticles, both Au and Ag in the suspension participate in the growth process. An attempt was also made to realize plasmon hybridization by reducing the volume of the suspension by simple evaporation. The nanochains were tested for application as SERS substrates by using crystal violet as probe molecules.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide