Selective Chemical Enhancement via Graphene Oxide in Infrared Attenuated Total Reflection Spectroscopy

Abstract

Graphene oxide (GO) as a readily prepared graphene derivative comprises negatively charged oxygenated functional groups, and a mixture of sp2 and sp3 carbon domains. In comparison with hydrophobic graphene, GO is characterized by superior water dispersibility, and may noncovalently interact with a significantly wider range of molecules. Taking advantage of GO and infrared attenuated total reflection spectroscopy (IR-ATR), an efficient strategy enabling unprecedented absorption signal amplification via chemical enhancement of various molecular species in aqueous environment was demonstrated in this study. The evolution of selectively enhanced molecular fingerprints across the entire mid-infrared spectral range was in situ monitored in real time, while retaining the characteristic molecular IR absorptions, and confirms the utility of GO as a suitable and versatile material in surface-enhanced infrared absorption spectroscopy (SEIRA) scenarios.