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

•Au nanoparticles electrodeposited on the ITO glass as SERS substrates.•Hierarchical Au nanostructures formed on the graphene oxide modified ITO glass.•Limit of detection (LOD) as low as 10−11 M for crystal violet dye.•Applicable to ultrasensitive label-free detection of chemicals and biomolecules.

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.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide