Facile fabrication of PS/Cu2S/Ag sandwich structure as SERS substrate for ultra-sensitive detection

In this work, a serials of PS(polystyrene)/Cu2S/Ag sandwich substrates were successfully constructed using the magnetic sputtering method by adjusting the Ag sputtering time (0 min, 2 min, 4 min, 6 min, 8 min and 10 min) and used as the surface-enhanced Raman scattering (SERS) substrates. When the Ag sputtering time was 6 min, the strongest SERS signal was observed. The optimized SERS substrate has strong SERS activity on 4-mercaptobenzoic acid (4-MBA), the minimum detection limit was 10(-13) M and the enhancement factor was as high as 4.7 x 10(7). In addition, the SERS signals were highly reproducible with small standard deviation. The SERS enhancement mechanism of the PS/Cu2S/Ag system was attributed to the synergistic effect of the chemical mechanism and the electromagnetic enhancement mechanism. This strategy has find a new way for manufacturing SERS activity sensor with high sensitivity and reproducibility. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A series of PS/Cu2S/Ag sandwich substrates were successfully constructed with strong SERS activity by adjusting the Ag sputtering time, and the optimum SERS signal was achieved with 6 minutes of sputtering. The SERS substrate showed a minimum detection limit of 10(-13) M and an enhancement factor of 4.7 x 10(7), with highly reproducible signals.