a paper-fiber-supported 3d sers substrate

Surface-enhanced raman scattering (sers) spectroscopy is an effective approach for trace-level detection of molecular substance. plasmonic metallic nanostructures with high distribution densities and small gap widths are always expected for constructing sers substrates. we report here a paper-based sers substrate, where the three-dimensional (3d) network of paper fibers was used as the platform for supporting the gold nanoparticle clusters. such a 3d arrangement of plasmonic porous clusters supplies high-density hotspots with large total volume and large surface area for the interaction with molecules. comparison between different papers found that the filter papers commonly available in labs are the best choice. an enhancement factor higher than 104 has been achieved in the detection of r6g molecules. the preparation of such sers substrates is very simple and convenient, implying low-cost, disposable, and environment-friendly sers techniques. furthermore, the paper-based flexible sers substrates can be easily tailored into different shapes and sizes for fitting different applications.