Studying the Effect of 2D Nanomaterials on Aluminum-Based Plasmonic Devices with TiO2-SiO2 Composite Layers for Biosensing Applications

Abstract

To achieve nano-scale efficient and label-free detection analysis, real-time sensing techniques have significantly prompted the surface plasmon resonance phenomenon to take center stage. Among plasmonic metals, aluminum (Al) stands out for its ability to deliver high detection accuracy across the entire electromagnetic wave spectrum. This study leverages the narrow linewidth of Al in the near-infrared region to enhance optical detection capabilities. By combining Al with a TiO2-SiO2 nanocomposite that enhances sensitivity furthermore, various 2D nanomaterials (graphene, molybdenum disulfide, MXene, and fluorinated graphene (FG)) are investigated using the transfer matrix method. Consequently, the resulting surface plasmon-based reflection curves are analyzed for key performance metrics, i.e., figure of merit (FOM) and sensitivity. The proposed configuration, consisting of TiO2-SiO2-Al-FG, is the optimal design demonstrated for biosensing applications as a proof of concept. All angle-based interrogations are performed within the optical communication window (1550 nm), ensuring a non-destructive approach for photo-sample analysis. With a sensitivity of 121°/RIU and an FOM of 490.57 RIU−1, our proposed configuration offers enhanced sensing capabilities and robustness, paving the way for real-world sensing applications.