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

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/H-2 (W18O49-H-2) exhibited stronger SERS signal than W18O49 nanowire films which resulted from the existence of more oxygen vacancies due to the reduction effect of H-2. The SERS detection limit of RB on W18O49-H-2 nanowire films reached 10(-7) M. And more importantly, the W18O49-H-2 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-H-2 nanowire film provides an important inspiration for its wide application in the detection of pollutants.