Novel electrochemical preparation of gold nanoparticles decorated on a reduced graphene oxide–fullerene composite for the highly sensitive electrochemical detection of nitrite†
In this study, we report a novel amperometric nitrite sensor based on a glassy carbon electrode (GCE) modified with gold nanoparticles (AuNP) decorated reduced graphene oxide–fullerene (RGO–C60) composite. The RGO–C60/AuNPs composite modified electrode was prepared via the electrochemical reduction of a GO–C60 composite modified electrode in pH 3 solution containing 5 mM gold(III) chloride trihydrate at the constant potential of −1.4 V for 200 s. The as-prepared materials were characterized using scanning electron microscopy, and Raman and Fourier transform infrared spectroscopy. Cyclic voltammetry results confirm that the RGO–C60/AuNPs composite modified electrode has high catalytic activity for the detection of nitrite compared with other modified electrodes. The RGO–C60/AuNPs modified electrode exhibits a stable amperometric response for nitrite in the liner concentration range of 0.05–1175.32 μM and its detection limit was estimated to be 0.013 ± 0.003 μM. The modified electrode shows high selectivity towards the determination of nitrite in the presence of potentially active common metal ions. In addition, the fabricated sensor exhibits many advantages for the detection of nitrite such as fast amperometric response, excellent operational and storage stability and appropriate practicality.