Titanium carbide MXene/silver nanostars composite as SERS substrate for thiram pesticide detection

Abstract

Two-dimensional transition metal carbonitrides, Ti3C2Tx MXene nanosheets, have drawn much attention due to their unique optical properties. These materials have huge potential to be employed as surface-enhanced Raman scattering (SERS) substrates. Herein, to combine the benefits of metal nanoparticles and MXene as SERS substrates, we prepared composite SERS films with different volume ratios composed of Ti3C2Tx MXene with silver nanostars (AgNs) as a promising SERS substrate for detection of pesticides. These SERS films were prepared via a drop-casting technique. The SERS activities of the MXene/AgNs composites were evaluated through detection of the thiram pesticide. MXene/AgNs exhibited the highest SERS intensity compared to MXene or AgNs substrate alone. Sampling from 20 different areas and samples of the substrate gave very consistent SERS signals. The MXene/AgNs substrate shows good stability for 1 month when stored in a small transparent container with silica gel. The MXene/AgNs SERS substrate exhibits excellent sensitivity able to detect thiram concentrations as low as 10−8 M which also having low a relative standard deviation (RSD) value for reproducibility and stability over a significant period.