MOF derived cobalt ferrite cubic rod-like materials for highly efficient electrochemical simultaneous detection of multiple heavy metal ions

A series of CoFe2O4 materials derived from metal-organic framework were successfully constructed by the solvent-thermal method. The morphology of a typical sample CoFe2O4-1 was mostly in the form of a cubic rod-like structure with a size distribution of 3.2 ± 0.2 μm, while a small amount of the structure presented hexagonal shape with uniform size dispersion. The XPS characterization results confirmed that the CoFe2O4-1 material contained Co3+ (Co2+/Co3+ = 0.98), and the redox reaction between Co2+ and Fe3+ produced more Fe2+ (Fe2+/Fe3+ = 1.63), leading to the production of more OV on the surface of the CoFe2O4-1 material (OV% = 0.34), thereby facilitating the efficient adsorption of the efficient adsorption of heavy metal ions (HMIs). CoFe2O4-1/GCE as a typical electrode presented excellent performance for the detection of multiple HMIs. The results should be attributed to the good electrical conductivity and large electrochemically active surface area of CoFe2O4-1/GCE, accelerating the transport of ions and charges in the system. Interestingly, there are interaction mechanisms between the HMIs when performing simultaneous detection, suggesting the detection of target ions can be facilitated by adding additional ions. This study provides new research insights for the development of highly sensitive electrochemical sensors for real-time environmental monitoring.