Thermally stable plasmonic nanocermets grown on microengineered surfaces as versatile surface enhanced Raman spectroscopy sensors for multianalyte detection

Abstract

Noble metal nanoparticle-based plasmonic sensors, fabricated by top-down and colloidal routes, are widely used for high sensitivity detection of diverse analyte molecules using Surface Enhanced Raman Spectroscopy (SERS). However, most of these sensors do not show stability under harsh environments, which limits their use as versatile SERS substrates. In this work, we report the first use of plasmonic nanocermets, grown on microengineered Si surfaces, as potential candidates for a highly robust SERS sensor. The robustness of the sensor is attributed to the anchoring of the nanoparticles in the nanocermet, which is an important factor for exploiting its reusability. The fairly uniform distribution of nanoparticles in the sensor led to high enhancement factors (10₆–10₇) and enabled the detection of low concentrations of a wide range of analytes, including differently charged biomolecules, which is extremely difficult for other SERS sensors. With more precise control over the particle geometry and distribution, plasmonic nanocermets may play an important role in ultrasensitive SERS measurements in adverse conditions such as high temperature.