TiO2 nanorod arrays decorated with Au nanoparticles as sensitive and recyclable SERS substrates

Surface enhanced Raman scattering (SERS) platforms with recyclability are highly required for the practical applications. In this work, TiO2 nanorod arrays decorated with Au particles (Au@TiO2 NRAs) are prepared by glancing angle deposition technology and subsequent gold sputtering. Au@TiO2 NRAs are demonstrated as sensitive SERS substrate while the optimal substrate with high reproducibility and stability is obtained. Illustrated by Frequency-domain finite element method (FEM), this excellent SERS performance can be attributed to the formation of high intensity hot spots located on the gap between Au nanoparticles. Moreover, the SERS substrates are extensively recyclable due to the well-known ability of TiO2 photocatalytic degradation of dye molecule under ultra-violet light. [Display omitted] •Au@TiO2 NRAs with sensitive SERS performance, high reproducibility and stability are prepared.•Illustrated by FEM, excellent SERS performance is attributed to the high intensity hot spots between Au nanoparticles.•SERS substrates are extensively recyclable due to the ability of TiO2 photocatalytic degradation.