Effect of electrodeposition cycles on the performance of gold nanostructures as SERS-active substrates

[Display omitted] Au nanoparticles (Au NPs) were electrodeposited on modified indium tine oxide (ITO) glass with different electrodeposition cycle numbers, as surface-enhanced Raman scattering (SERS) substrates. The optimized Au nanostructures on the ITO glass exhibited the good reproducibility and very low detection limit of 10−10M for CV and 10−9M for dopamine. Au nanostructures electrodeposited on amine-terminated indium tin oxide (ITO) glass as surface-enhanced Raman scattering (SERS) substrates. The number of electrodeposition cycles (one cycle consists of a nucleation potential of 0.7V for 2s and a growth potential of −0.3V for 1000s) were optimized. Among as-prepared substrates (1–10 cycles), Au nanostructures formed by three cycles yielded the highest Raman signals of probe molecules, owing to their rough surface morphology with multiple inter-space nanogaps. The Au nanostructure exhibited the very low detection limits of 10−10M for crystal violet and 10−9M for dopamine, as an ultrasensitive SERS substrate.