Composition and architecture-engineered Au–SnO2/GNs-SWCNTs nanocomposites as ultrasensitive and robust electrochemical sensor for antioxidant additives in foods

The Au–SnO 2 /graphenes (GNs)-single-walled carbon nanotubes (SWCNTs) nanocomposite has been prepared through green chemistry methods. This composite material was deliberately designed to combine the virtues of metal, semiconductor, and carbon materials. Its successful formation has been confirmed by a series of characterizations, such as transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). A new electrode based on this nanocomposite was fabricated and used as a voltammetric sensor for detection of 2-tert-butylhydroquinone (TBHQ) through cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. Under optimized conditions, this electrode presents a linear response in a broad concentration range of 5.0   ×   10 −8 to 2.3   ×   10 −4   M of TBHQ, with its detection limit reaching 5.8   ×   10 −8   M. This simultaneous broad-range and ultrasensitive detecting capability for TBHQ is, to our best knowledge, better than all the previously reported modified electrodes. The excellent performance is attributed to the synergistic effects among the constituent nanomaterials (GNs, SWCNTs, SnO 2 , and Au) and the unique nano-architecture of this nanocomposite.