An assembled ordered W18O49 nanowire film with high SERS sensitivity and stability for the detection of RB

Abstract

In this work, a novel ordered nanowire film composed of non-stoichiometric semiconductor metal oxide, W18O49, was assembled by a three-phase-interface approach. The prepared W18O49 nanowires possess relatively uniform morphologies with average diameter of about 10 nm. When employed as the SERS substrate for the detection of rhodamine B (RB), the ordered W18O49 nanowire film calcined in Ar/H2 (W18O49-H2) exhibited stronger SERS signal than W18O49 nanowire films which resulted from the existence of more oxygen vacancies due to the reduction effect of H2. The SERS detection limit of RB on W18O49-H2 nanowire films reached 10−7 M. And more importantly, the W18O49-H2 nanowire film SERS substrate possessed outstanding reproducibility for detecting RB because of the ordered as well as stable morphology, reflecting in the low relative standard deviation (RSD) (9.7%). Therefore, as a new non-noble metal SERS substrate, the W18O49-H2 nanowire film provides an important inspiration for its wide application in the detection of pollutants.