In situ preparation of FeSe nanorods-functionalized carbon cloth for efficient and stable electrochemical detection of nitrite

In this paper, a self-supported electrode for nitrite detection was obtained by loading ferrous selenide nanorods on carbon cloth (FeSe NR/CC) via in situ synthesis. The morphology and chemical composition of the FeSe NR/CC were characterized using scanning electron microscope (SEM), X-ray diffractogram (XRD), and X-ray photoelectron spectroscopy (XPS). Owing to the synergistic effect between FeSe nanorods and carbon cloth, the rich redox active sites, and the lower transferring resistance, the binder-free and self-supported sensor based on FeSe NR/CC exhibits a wide linear relationship from 0.625 μM to 6775.5 μM, a fast-current response of 3 s, and a high sensitivity of 1107.7 μA mM−1 cm−2. The detection limit of the FeSe NR/CC was evaluated as 0.07 μM and the developed sensor displays excellent selectivity, stability, and reproducibility. Additionally, the as-prepared sensor has been successfully applied to detect nitrite in pickled vegetable samples, proving its feasibility for practical applications. Therefore, the self-supported and binder-free electrode proposed in this study could be used as a highly efficient and cost-effective electrochemical nitrite sensing device to achieve rapid quantitative detection of nitrite in food samples.