Electrochemical growth of dendritic silver nanostructures as facile SERS substrates

We successfully prepared silver dendritic nanostructures with a well-defined and precisely tailored trunk and branches, as well as decorated nanoparticles, by a simple and controllable two-electrode electrochemical deposition system using different AgNO3 concentrations and deposition potentials. The prepared nanostructures are used as SERS substrates for the detection of crystal violet molecules with a minimum detection limit of 10-11 M. Finite-difference time-domain (FDTD) simulation is used to analyze the SERS activity of diverse silver dendritic nanostructures. The SERS and FDTD results revealed that the pine leaf-like structure displays excellent sensitivity and reproducibility compared to all other structures due to a large number of hotspot sites between branch-branch and branch-particle junctions. This article provides a good understanding of electromagnetic field enhancement and shows that various silver dendritic nanostructures could be potential candidates for SERS-based detection.