Facile fabrication of Ag/graphene oxide/TiO2 nanorod array as a powerful substrate for photocatalytic degradation and surface-enhanced Raman scattering detection

A novel graphene oxide/TiO2 nanorod array (GO/TNR) decorated with Ag nanoparticles (NPs) is successfully prepared as a photocatalyst and a surface-enhanced Raman scattering (SERS) substrate for organic molecule detection. The as-obtained Ag/GO/TNR sample exhibited a large specific surface area and high adsorption capacity toward Rhodamine 6G (R6G) molecules. Moreover, the GO interlayer with suitable content had a significant effect on the absorption intensity of light and Raman signals for the Ag/GO/TNR substrate. For R6G as probe molecules, the Ag/GO/TNR substrate with 5 min of GO-deposition achieved a lower detection limit of 1.0 × 10−12 M and an improved enhancement factor (EF) of 5.86 × 105 as compared to other films. Furthermore, the relative standard deviation (RSD) value of the Raman vibration at 1650 cm−1 cm was approximately 8.71%, and the good uniformity remained. Using Xenon lamp irradiation, the outstanding photocatalytic ability endowed the substrate with good self-cleaning and reusable properties. Based on the above results, a synergistic effect of three components (Ag NPs, GO interlayer, and TNR) is proposed to produce an excellent SERS performance, namely, a large adhesion area, the interaction of excited photons, and high-density hotspots in the active substrate.