Creating SERS hot spots on ultralong single-crystal β-AgVO3 microribbons

Abstract

β-AgVO₃ ribbons are novel one-dimensional structures with excellent structural, electrical, and catalytic properties. Here we report the synthesis of ultralong β-AgVO₃ microribbons and their applications as surface-enhanced Raman scattering (SERS) substrates. A hydrothermal method allows us to prepare millimeter-long β-AgVO₃ ribbons with a cross-section of ∼2.5 μm × ∼1 μm in a high yield. The length of the β-AgVO₃ microribbons is controlled by the amount of pyridine added to AgNO₃ and NH₄VO₃. The perfectly smooth and single crystalline β-AgVO₃ surfaces drastically change into rough and rippled surfaces upon reaction with 4-aminothiophenol. Electron microscopy studies reveal that Ag nanoparticles with a diameter of ∼7 nm are formed on the surface, rendering the ultralong β-AgVO₃ microribbons highly SERS-active. Possible mechanisms of the transformation and applications of the resulting SERS-active substrates in microfluidics are discussed herein.