Graphene Aerogel Decorated with MoS2 Sheets: an Efficient Electrochemical Sensing Platform for Caffeic Acid in Red Wine Sample

As a typical two-dimensional (2D) transition metal disulfide, molybdenum disulfide (MoS2) shows good electrocatalytic activity, and is considered as a promising sensing material due to its adequate exposed active edges. However, 2D sheet-like structural MoS2 tends to aggregate, resulting in a decreased specific surface area. In addition, the poor electronic conductivity of MoS2 limits the electrochemical application. To address these issues, herein, graphene aerogel (GA), with a three-dimensional (3D) nanoarchitecture consisting of a large specific surface area, rapid electron transfer, and excellent electrocatalytic activity, has been employed as a novel framework support for MoS2. Through a facile one-step hydrothermal technique, the peeled MoS2 sheets were incorporated into the GA network. The MoS2/GA composite was investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The composite combined the excellent electrical conductivity and huge effective surface area of GA with the high catalytic activity of the MoS2 nanosheets. Due to these advantages, the MoS2/GA composite was applied as an electrochemical sensing platform for caffeic acid (CA) detection. The sensor performed good selectivity, wide linear range (1.0 nM-10.0 mu M), and low limit of detection (LOD, 0.3 nM). Furthermore, the designed sensor represented good reproducibility and stability, and was successfully applied for detecting CA in red wine samples.