ZIF-derived Co nanoparticles embedded into N-doped carbon nanotube composites for highly efficient electrochemical detection of nitrofurantoin in food.

[Display omitted] • N/Co@CNTs@CC was prepared by sublimation-gas phase transition strategy. • N/Co@CNTs@CC exhibits uniform N doping, hollow structure and active metal sites. • The growth mechanism of N -doped carbon nanotubes was investigated. • N/Co@CNTs@CC has excellent feasibility in food samples. Designing efficient and sensitive methods for the detection of nitrofurantoin (NFT) residues is of great importance for food safety and environmental protection. Herein, a composite with cobalt nanoparticles encapsulated in nitrogen-doped carbon nanotube (N/Co@CNTs@CC-II) was synthesized by in-situ growth and sublimation-gas phase transformation strategy and used to establish an ultrasensitive electrochemical sensor for NFT determination. The N/Co@CNTs@CC-II sensor exhibits uniform N doping, fine hollow structure, and abundant active metal sites, which lays a solid foundation for the ultra-sensitive detection of NFT. Benefiting from these advantages, the N/Co@CNTs@CC-II exhibits excellent sensitivity (8.19 μA μM−1 cm−2) and low detection limit (18.41 nM) for NFT detection. The practical feasibility of N/Co@CNTs@CC-II was also demonstrated by the determination of NFT in milk and tap water samples. This study may open up new opportunities for the application of N -doped carbon nanotube materials encapsulating transition metals. [ABSTRACT FROM AUTHOR]