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.

Highly Stable, Graphene-Wrapped, Petal-like, Gap-Enhanced Raman Tags

“…According to the principle of electromagnetic field enhancement, the approximate electromagnetic enhancement factor ( EF EM ) can usually be calculated with the following formula [ 45 ]: where is the incident electric field strength, which is usually set to 1 V/m. is the local electric field strength of incident light (frequency ), and is the local electric field strength of Raman scattered light (frequency ).…”

Capillary Tube Surface-Enhanced Raman Scattering Substrate and High-Sensitivity Molecule Detection

“…On the other hand, a strong local field by LSPR sometimes causes several photochemical reactions, adhesion, or agglomeration of analyte molecules on metal nanoparticles during SERS measurement. , It is reported that the deposition of TiO 2 between the substrate and metal nanoparticles makes the SERS substrate recyclable. By ultraviolet light irradiation, TiO 2 induces photocatalytic degradation of analytes molecules. , This approach would be an effective approach to make this capillary tube tip recyclable. Our method would be a powerful tool, especially for environmentally hazardous substance detection, health care, or food analysis, where the sample volume and the concentration are extremely low.…”

“…By ultraviolet light irradiation, TiO 2 induces photocatalytic degradation of analytes molecules. 27,28 This approach would be an effective approach to make this capillary tube tip recyclable. Our method would be a powerful tool, especially for environmentally hazardous substance detection, health care, or food analysis, where the sample volume and the concentration are extremely low.…”

Highly Sensitive, Robust, and Recyclable TiO2/AgNP Substrate for SERS Detection

“…Jiang et al grew AgNPs on the surface of TiO 2 nanospheres to complete a self-cleaning function. They exhibited an LOD lower than 10 −12 mol/L for rhodamine 6G (R6G) molecule in a recyclable manner [ 30 ]. Other Ag-TiO 2 -based recyclable SERS substrates are reported in references [ 31 , 32 , 33 ].…”