Surface potential and morphology mapping to investigate analyte adsorption effects on surface enhanced Raman scattering (SERS)

Abstract

We demonstrate the power of Kelvin probe force microscopy (KPFM) in enabling a comprehensive study of enhancement mechanisms of surface enhanced Raman scattering (SERS) through the correlation of surface electrical and topographical effects. Local electric fields generated on Au/ZnO nanohybrid films impact analyte adsorption, while roughness is linked to hotspot generation. Optimizing the interplay between these two effects yields SERS enhancement factors (EFs) of 10⁶, enabling ppb detection of polycyclic aromatic hydrocarbons (PAHs) in water.