Multifunctional Porous Nanohybrid Based on Graphene-Like Tungsten Disulfide on Poly(3,4-ethoxylenedioxythiophene) for Supercapacitor and Electrochemical Nanosensing of Quercetin

Abstract

A multifunctional porous nanohybrid was designed for supercapacitor and nanosensor for voltammetric detection of Chinese traditional herbal drug quercetin (Qu) extracted from lotus leaves using graphene-like tungsten disulfide (WS2) nanosheet onto a porous and conductive poly(3,4-ethoxylenedioxythiophene) (PEDOT). Conducting PEDOT with a rough, porous, irregular surface was synthesized by one-step electropolymerization of commercially available monomer in acetonitrile solution, then WS2/PEDOT was facilely obtained by drop-coating WS2 nanosheet dispersion onto the synthesized PEDOT. WS2/PEDOT porous nanohybrid displayed a high capacitance characteristic with specific capacitance of 70.64 F·g−1 at a current density of 0.2 A·g−1, good cycling stability with capacitance retention of 90.74% after 5000 cycles and excellent voltammetric responses for Qu in linear ranges from 1.5 × 10−7 to 1 × 10−4 mol l−1 with a limit of detection (LOD) of 50 nM and sensitivity of 1.76 μA μm−1 cm−2 under the optimum operation conditions. The developed nanohybrid sensor was employed for the electrochemical detection of Qu in real sample with acceptable recoveries in comparison with high-performance liquid chromatography. This work will provide an experimental basis for nanosensing platform integrated with supercapacitor as self-powered electrochemical energy storage system in the near future.