One-pot hydrothermal synthesis of ZnO/RGO/ZnO@Zn sensor for sunset yellow in soft drinks.

ZnO/RGO/ZnO nanocomposite was in-situ anchored on Zn foil through a simple one-step hydrothermal approach. Based on the redox reaction between graphene oxide (GO) and Zn foil, and the electrostatic attraction between the negative-charged GO and positive-charged zinc ions, three strong interfaces of ZnO/RGO, RGO/ZnO and ZnO/Zn were simultaneously constructed, which led to improved electron and ion transfer. As-prepared ZnO/RGO/ZnO@Zn directly acted as sensor for amperometric detection of sunset yellow without further assembling, which exhibited an ultrahigh sensitivity of 20.25uAμM-1cm-2, a low limit of detection (3nM), a wide linear detection ranging from 0.01 to 5µM.