Enhanced non-enzyme nitrite electrochemical sensing property based on stir bar-shaped ZnO nanorods decorated with nitrogen-doped reduced graphene oxide

A novel stir bar-shaped ZnO (sb-ZnO)/nitrite-doped reduce grapheme oxide (N-rGO) nanocomposite (sb-ZnO/N-rGO) was facilely synthesized by using the hydrothermal route. Furthermore, a glassy carbon electrode (GCE) modified with the sb-ZnO/N-rGO nanocomposite was constructed and used as the non-enzymatic nitrite electrochemical sensor (sb-ZnO/N-rGO/GCE). Benefiting from the excellent catalytic activity to the electro-oxidation of nitrite as a result of the synergy of N-rGO and sb-ZnO, the modified electrode displayed a superior amperometric sensing performance toward nitrite detection including lower detection limit (LOD) of 0.13 μM, broad linearity range of 0.2 μM~1.2 mM and 1.5–7.8 mM, high sensitivity, rapid response, remarkable repeatability, outstanding durability, good storage stability and strong resistance against interfering substance. In addition, this sensor showed satisfying recovery between 96.0% and 103.0% to nitrite in practical application involved ham sausage, pickled vegetables as well as tap water. The as-synthesized sb-ZnO/N-rGO composite is a qualified candidate for fabricating nitrite electrochemical sensor, which would have promising application prospect in terms of food analysis and environmental monitoring.