Investigation of Hydrophobic Bimetallic Cost-Effective Cu-Ag Nanostructures as SERS Sensor

Surface-enhanced Raman spectroscopy (SERS) has shown a strong Raman enhancement with bimetallic nanoparticles. The combination of the different bimetallic nanoparticles is used in the field of SERS sensors. These sensors can resonate with the organic molecules adsorbed on their surfaces for SERS enhancement. Fabricating these bimetallic, cost-effective and ultrasensitive SERS sensors is a great challenge. To overcome this challenge, a rapid fabrication method of ultrasensitive noble SERS sensors that enable sub-femtomolar detection of molecular analytes, is reported here. SERS sensor is obtained by application of the silver nanorods (AgNRs) deposited on copper nanoflowers (CuNFs) fabricated by chemical reduction and chemical etching, respectively. Purity and structural characteristics of the SERS sensor are measured qualitatively by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, UV-visible spectroscopy, X-ray diffraction, Fourier transform infrared microscopy and Raman analysis. Rhodamine 6 g as an analyte analyses the sensitivity of the SERS sensor. The detection limit and enhancement factor are found to be 10−13 M and 109 respectively for AgNRs deposited CuNFs etched for 30 min. This study reveals that the AgNRs deposited CuNFs are practically found to be sensitive SERS sensors.