Surface nanostructuring and wettability of low energy Ar+ irradiated Au/ V2O5/Au multilayer system for SERS detection of rhodamine-6G

Detection of rhodamine-6G by SERS (Surface Enhanced Raman Scattering) on different-thickness of oxide layer sandwiched between gold (Au) layers exposed to an ion beam is reported. Thermal evaporation was used to deposit Au/V2O5/Au multilayers of varying V2O5 thicknesses (5 and 10 nm) on a glass substrate. After being exposed to 10 keV Ar+ at varying fluences, the surface morphology can be tuned with development of Aunanostructures (Au-NS). The growth of Au-NS is governed by ion beam-induced sputtering and diffusion mechanisms. In addition to validating the thickness of oxide layer, Rutherford Backscattering Spectroscopy (RBS) confirms the elemental composition of Au/V2O5/Au on the glass substrate. Sputtering and surface diffusion are two competing statistical elements that determine the wettable properties of Au-NS surfaces. A relationship between rms roughness, water contact angle, and the detection of rhodamine-6G (R6G) by surface enhanced Raman scattering (SERS) is provided. Understanding the mechanism(s) through which SERS chemical detection works on metallic-oxide multilayer system is advanced by the present study.