Hierarchical Au nanostructure electrodeposited on graphene oxide⿿Modified ITO glass as an ultrasensitive SERS substrate

Abstract Hierarchical Au nanostructures electrodeposited on an indium tin oxide (ITO) glass modified with graphene oxide (GO) (GO_ITO) as surface-enhanced Raman scattering (SERS) substrates to detect crystal violet (CV) dyes. The electrodeposition process performed using a double-potential method with three electrodes. Au nanostructures deposited on the GO_ITO glass by adjusting operating parameters during the electrodeposition process. The GO_ITO glass exhibited a significant variation of the surface morphology and packing density of Au nanostructures depending on the growth potential and deposition time. The optimized Au nanostructures demonstrated a detection limit of crystal violet as low as 10⿿11 M, due to the high packing density and hierarchical nanostructures with protruding nano-edges. The significant enhancement in SERS measurements demonstrates that these nanostructures are capable of an ultrasensitive label-free detection of chemicals and biomolecules.