An Ultrasensitive, Disposable, and “Plug and Play” Surface-Enhanced Raman Scattering Substrate for the In Situ Detection of Trace Thiram in Water

In this work, TiO2 nanotube arrays were fabricated on Ti meshes via anodic oxidation and decorated with Ag nanoparticles by a photodeposition process. Then the surface-enhanced Raman scattering (SERS) effect of the as-prepared samples for trace thiram was directly investigated in a thiram aqueous solution. The stability and selectivity of our substrates were also explored. In addition, for practical purposes, we further studied the SERS of trace thiram in tap water using the as-prepared sample as a SERS substrate. At last, the surface-enhanced mechanism was discussed preliminarily. It can be found that the Ag-nanoparticle-decorated TiO2 nanotube array on a Ti mesh is an ultrasensitive SERS substrate for trace thiram in water. The detection limits are up to 1 × 10–9 mol L–1 in deionized water and 1 × 10–7 mol L–1 in tap water, respectively. Moreover, this substrate possesses dramatic signal uniformity [relative standard deviation <6% (spot-to-spot)], excellent reproducibility [relative standard deviation <4.7% (batch-to-batch)], high selectivity, and good stability. These results indicate that this inexpensive substrate possesses great potential as a highly sensitive, disposable, and “plug and play” SERS substrate for the in situ detection of trace thiram in drinking water.