Development of Plasmon Resonance Sensing Based on Alkylthiol-Coated Triangular Silver Nanoplates on Glass Plates

Abstract

In this study, we have developed localized surface plasmon resonance (LSPR) refractive index sensor systems consisting of triangular silver nanoplates (nanoprisms) immobilized on glass plates by electrostatic interactions. The nanoprisms are synthesized by exploiting light-induced morphological changes in silver nanoparticles in aqueous solution. We have demonstrated that silver nanoprisms protected with alkylthiol molecules and supported by glass plates can function as spectrally stable LSPR refractive index sensors even in ethanol solvents. The sensitivity of the nanoprisms was found to increase with decreasing carbon chain length of alkylthiol. Furthermore, we have demonstrated that nanoprisms with higher aspect ratios had higher sensitivities than those with lower aspect ratios.