Using Ag-embedded TiO2 nanotubes array as recyclable SERS substrate

A simple strategy for synthesizing Ag-loaded TiO2 nanotube film for use as multifunctional photocatalyst and recyclable surface-enhanced Raman scattering (SERS) substrate is introduced. Highly aligned TiO2 nanotube arrays (TNTA) prepared via electrochemical anodization were used as a 3D rough host for silver nanoparticles. Ag deposits were sputtered in a vacuum, and it was found that their morphologies were mainly influenced by the diameters of nanotubes and the UV irradiation induced aging process, especially the self-migration of silver along the tubular wall. SERS and the self-cleaning effect were observed using Rhodamine 6G (R6G) as the probe molecule. The results showed that narrow nanotube and silver nanoparticles embedment contributed significantly to both the phenomenal SERS and recyclability.