SERS effect of Rhodamine 6G molecular probe on AgAu alloy nanowire arrays by a solid-state ionics method

Abstract

AgAu alloy nanowire arrays were prepared by a solid-state ionics method under a direct current electric field (DCEF) using fast ionic conductor RbAg4I5 films. The surface morphology and chemical composition of the AgAu alloy nanowire arrays were characterized by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), respectively. Raman enhancement performance of the AgAu alloy nanowire arrays substrates was detected by Rhodamine 6G (R6G) aqueous solutions as molecular probe. Long-range order and short-range order AgAu alloy nanowire arrays with the length of 1 cm were prepared by a solid-state ionics method. The nanowires were bamboo-shaped and the diameters of nanowires ranged from 20 to 80 nm. The molar ratio of Ag to Au is 15:1. The limiting concentrations of R6G for the prepared AgAu alloy nanowire arrays SERS substrates is 10−17 mol/L. The long-range and short-range orderly arrangement, high roughness and alloy structure of AgAu alloy nanowire arrays result in the substantial SERS effect.