Ag nanoparticle ink coupled with graphene oxide cellulose paper: a flexible and tunable SERS sensing platform.

Surface-enhanced Raman scattering (SERS) is highly promising for ultra-sensitive detection in a series of applications. Although extensive advances have been achieved in SERS technologies, the preparation of highly efficient SERS substrates still suffers from several limitations, including complex preparation procedures, high cost, and instability for long time storage. To address these problems, we report a novel, to the best of our knowledge, SERS platform that combines graphene oxide (GO) and cellulose composite paper with colloidal silver nanoparticle (Ag NP) ink. As an efficient substrate, the GO and cellulose composite paper that features hierarchical micro-nanostructures and improved interaction with target molecules can be fabricated on a large scale, and the Ag NP ink can be well stored, avoiding being oxidized in ambient conditions. In this way, our SERS platform not only reduces the cost, but also improved the stability. The sensitivity, reproducibility, and tunable SERS detection performance were evaluated using rhodamine 6G as probing molecules. To demonstrate the capability of our SERS platform in practical analysis, the SERS spectra of two monosodium salt solutions of different concentrations have been collected. The SERS platform has revealed great potential for practical application of SERS technologies.