Preparation of Ni, Co doped hollow carbon nanocage from core-shell structure ZIF-8@ZIF-67 for nitrobenzene monitoring

Herein, we employed a Ni, Co duplex metal-doped hollow carbon nanocage derived from the core-shell Zeolite imidazole framework-8 (Zn)@Zeolite imidazole framework-67 (Co) (ZIF-8@ZIF-67) for the sensitive electrochemical detection of nitrobenzene (NB). The precursor was created by coating ZIF-67 on the surface of ZIF-8 through the epitaxial growth method, followed by Ni doping. Subsequent pyrolysis resulted in the formation of a Ni, Co duplex metal-doped hollow carbon nanocage. Characterization of the nanocomposite confirmed the unique hollow and porous structure of NiCo/C, maintaining a dodecahedral morphology with a uniform distribution of carbon and transition metal nanoparticles. The NiCo/C-modified electrode exhibits a wide linear dynamic range (0.05–11.22 μM and 11.22–230.06 μM), a lower limit of detection (0.14 μM), superior stability and selectivity for the detection of NB. Moreover, it shows appropriate practicality toward detecting NB in natural water samples.