Nanomechanical Recognition and Discrimination of Volatile Molecules by Au Nanocages Deposited on Membrane-Type Surface Stress Sensors

Abstract

Here, we show that gold nanocages (AuNCs) can be used as receptor materials for nanomechanical membrane-type surface stress sensor (MSS). The fabricated AuNCs-coated MSS (AuNCs_MSS) was employed successfully for the recognition of small volatile molecules. Each AuNCs_MSS exhibited a specific pattern of the response signal to each analyte, enabling groupwise discrimination of the compounds by means of principal component analysis (PCA). The application of contour maps of analyte-distinctive features on the PCA plots allows us to recognize polarity as a key property that affects the AuNCs_MSS response. In addition, density functional theory (DFT) calculations suggest that corners and edges of the nanocages play important roles in binding energy.