Low-cost Au nanoparticle-decorated cicada wing as sensitive and recyclable substrates for surface enhanced Raman scattering

A large-scale, low-cost and three-dimensional biomimetic surface enhanced Raman scattering (SERS) substrate with vast and regular 'hot spots' was prepared by the deposition of gold (Au) nanoparticles on the bioscaffold arrays of cicada wings by the electron beam evaporation. Characterizations of the formed three-dimensional Au/cicada wing nanostructure proved that it owns outstanding SERS properties of highly active sensitivity, good uniformity and repeatability. The SERS limit of detection (LOD) for Rhodamine 6G reaching as low as 10−7 M, and a Raman enhancement factor being as large as 105 with a relative standard deviation of 10.1% were obtained. More importantly, this substrate has a good recyclability by the simple NaBH4 washing. For the application of Au/cicada wing, thiram was also detected rapidly and quantitatively with a LOD as low as 10−7 M. Our findings are beneficial in the application of SERS substrate, allowing quantitative and recyclable detection of trace organic contaminants and making it very promising in the label-free detection of biological molecules.