Synthesis of CoFe 2 O 4 @C based on Fe/Co-BTC for efficient detection, determination and degradation of nitenpyram residue: An electrochemical study, condition optimization and mechanism

As a widely-used neonicotinoid insecticide, nitenpyram is widely used in agricultural production due to its high efficiency, low toxicity and broad-spectrum insecticidal properties. However, its residue poses a potential threat to the environment and ecosystem. In this study, a new material with a core-shell structure, namely CoFe 2 O 4 @C, prepared based on Fe/Co-BTC was successfully developed for the efficient detection and degradation of nitenpyram. CoFe 2 O 4 @C exhibited excellent detection performance in the concentration range of 10 −4 to 10 −12  mol/L by differential pulse voltammetry (DPV) with high sensitivity (LOD = 845 fM) and good linearity ( R 2  = 0.9952). CoFe 2 O 4 @C also demonstrated high recoveries in real sample analyses, validating its reliability for in situ detection. In addition, it was found that CoFe 2 O 4 @C was able to efficiently promote the degradation of nitenpyram in the electro-Fenton system at a concentration of 10 mg/L under optimized conditions in only 20 min. In conclusion, CoFe 2 O 4 @C excelled in the detection of nitenpyram with its stability, reproducibility, and immunity to interference, and also demonstrated efficient performance in the electro-Fenton degradation process. Relative mechanism and pathway of CoFe 2 O 4 @C for the detection and degradation of nitenpyram have been investigated. These results not only provide a new technology for the environmental monitoring of nitenpyram, but also contribute an effective technological tool in the field of pollution control.