Multilayered Au nanorod arrays for surface enhanced Raman and infrared absorption spectroscopies

In this study, we will present the synthesis of self-assembled coupled Au nanorods (NRs) as substrates capable of supporting a dual modality of surface enhanced spectroscopies, SERS and SEIRAS. The AuNR arrays can be assembled either through vertical alignment or lateral alignment. We will present different assembly strategies for the Au NRs by adjusting the ionic strength of the Au NR solution. The goal is to rely on self-assembly to create organized and reproducible sensors for small molecule detection. Field enhancement criteria differs between SERS and SEIRAS. We will also present the finite-difference time-domain (FDTD) simulation of the multilayered AuNR array across visible and SWIR spectral region to explain some of the experimental observations.