TiO2/AgNPs SERS substrate for the detection of multi-molecules with a self-cleaning and high enhancement factor using the UV-induced method

Abstract

An ultraviolet light-induced method is used to simultaneously grow silver nanoparticles (AgNPs) on the surface of titanium dioxide (TiO2) nanospheres and complete a self-cleaning function. By adjusting ultraviolet (UV) light-induced duration, TiO2/AgNPs composite samples were prepared as surface-enhanced Raman scattering (SERS) substrates. The electromagnetic distribution of TiO2/AgNPs was analyzed with FDTD Solutions simulation software, and the corresponding theoretical enhancement factor was calculated. Taking the Rhodamine 6G (R6G) molecule as an analyte, the experimental detection limit is lower than 10−12 mol/L under UV-induced duration of 10 min, and the analytical enhancement factor (AEF) is ∼ 6.8×1010. In addition, the UV light-induced used samples can show a self-cleaning function, and the samples can be used for 5 cycles, with certain stability and repeatability. Moreover, the samples’ performance of multi-molecule detection is experimentally carried on.