Reusability Long-Life Storage and Highly Sensitive Zirconium Nitride (ZrN) Surface-Enhanced Raman Spectroscopy (SERS) Substrate Fabricated by Reactive Gas-Timing Rf Magnetron Sputtering

Abstract

Transition metal nitrides (TMN) are promising material alternative to replace noble metals in the field of plasmonic applications especially surface-enhanced Raman spectroscopy (SERS). Here we demonstrate a practical surface enhanced Raman spectroscopy (SERS) substrate using zirconium nitride (ZrN) thin films grown by reactive gas-timing (RGT) rf magnetron sputtering. The tailored properties of ZrN thin film exploited for SERS activity could be achieved to obtain a highly sensitive ZrN thin film SERS substrate with the enhancement factor (EF) of 1.24��6 and 4.8 %RSD at 1626 cm-1 toward methylene blue (MB) analyte which are comparable to the optimized Au sputtered thin films (EF=1.18��6 and with 5.1%RSD). We find that the spatial plasmonic hotspots on the surface of ZrN SERS substrate controlled by the turn-on timing of Ar:N2 sputtered gas sequence leading to the discrete conductive surface profile strongly relates to non-stoichiometric composition and the degree of (200)-oriented texture at the surface of ZrN thin film. Furthermore ZrN thin film SERS substrates exhibit an excellent recyclability more than 30 cycles with simple cleaning process and a storage time longer than 6 months. The detection and reusability of ZrN SERS substrate on the low concentration of trinitrotoluene (TNT) for homeland security are also performed. ? 2023 The Authors. Advanced Materials Interfaces published by Wiley-VCH GmbH.