SERS-active composite based on rGO and Au/Ag core-shell nanorods for analytical applications

•A new method to synthesize the functional hybrid material composed of reduced graphene oxide and Au/Ag core-shell nanorods used as SERS sensor.•This facile and powerful SERS sensor detected rhodamine-6G (R6G) with an enhancement factor as high as ∼ 5.03 × 108.•RGO-Au@AgNRs can also be used to monitor the pesticide thiram at low level ∼10−7 M and was with relative standard deviation (RSD) is about 7.5%, 17.3% and 15.1% at 561 cm−1, 962 cm−1 and 1389 cm−1, respectively.•RGO-based is flexible, and its size and shape can be adjusted depending on the requirements.

This work demonstrated a new method to synthesize the functional hybrid material composed of reduced graphene oxide and Au/Ag core-shell nanorods (rGO-Au@AgNRs). The hybrid material can detect rhodamine-6G (R6G) with an enhancement factor (EF) up to (5.0 ± 0.2) × 108, 4 fold higher than that of the rGO-AuNRs. Comparing with SERS-active substrate Au@Ag (without rGO), the Raman intensity of R6G on the rGO-Au@AgNRs has significant enhancement, especially at the Raman peak of 611 cm−1, around 17 times. We also use rGO-Au@AgNRs to monitor the pesticide thiram at a low level ∼10−7 M and RSD 7.5% at the 561 cm−1. The limit of detection (LOD) of thiram using rGO-Au@AgNRs was low to 5.12 × 10−3 μM, which suggested that the rGO-Au@AgNRs has potential applications in the detection of environment pollutants etc.