Porous Tungsten Nitride: A Sensitive SERS Substrate with High Stability

In surface-enhanced Raman spectroscopy detection, the structure of the Raman scattering substrate is critical to the sensitivity and stability of the detector. In this study, W18O49 ultrafine nanowire bundles are used as precursors to synthesize porous tungsten nitride (WN) through a nitriding treatment. As a typical transition metal nitride (TMN), these porous WN exhibit a strong localized surface plasmon resonance effect in the visible region, with a resonance peak centered at 672 nm. Significantly, WN as a substrate for detection of typical dyes exhibit strong Raman enhancement signals. In particular, the detection sensitivity for R6G has been significantly improved, with the lowest detectable concentration reaching an impressive 1 × 10-10 M, and the maximum enhancement factor is up to 1.62 × 107. Moreover, they even can maintain the detection performance in a variety of harsh environments, showing outstanding corrosion resistance, and oxidation resistance, which is not available on traditional noble metal and semiconductor Raman substrates.