Integrating electrochemical sensor based on MoO/CoO heterostructure for highly sensitive sensing of nitrite in sausages and water.

Considering excess nitrites are detrimental to the human body and environment, designing a rapid, sensitive, and real-time quantitative determination for nitrite is of great significance for environmental preservation and public health. In this paper, CoO nanoflowers coupled with ultrafine MoO nanoparticles (MoO/CoO) are obtained via a hybrid electrochemical deposition strategy (HED). The as-designed MoO/CoO/CC integrating electrode exhibits superior electrocatalytic properties towards nitrite oxidation, owing to the synergistic effect between MoO and CoO caused by the heterostructure of MoO/CoO. The electrode achieved a low response time of 2 s, an excellent sensitivity of 1704.1 μA mM cm, and a low limit of detection of 0.075 μM (S/N = 3). Furthermore, the electrode displays promise for nitrite detection in complex food such as water and sausages samples. Our study will provide a significant strategy for the application of bimetallic heterostructure to explore the design of sensing interfaces.