Metal-organic-framework-derived Ni3ZnC0.7 materials for highly sensitive electrochemical detection of catechol

Catechol is one of the main compounds causing phenolic contamination in water. It has significant harmful effects on human health and the environment. It has been challenging to develop a simple and sensitive electrochemical method for the detection of catechol. In this study, metal–organic framework (MOF)-derived Ni3ZnC0.7 composites were prepared, and their electrocatalytic activity was investigated. Moreover, they were applied to the electrochemical detection of catechol for the first time. Subsequently, the physicochemical properties of Ni3ZnC0.7 were investigated. The Ni3ZnC0.7 composites had a large specific surface area and exhibited abundant porosity, high electrical conductivity, and excellent electrocatalytic properties. This high performance was attributed to the formation of electroactive functional groups on the electrode surface during the electrochemical activation and the synergistic effects between Ni and Zn. Under the optimized conditions (pH 7.5; drop-coating amount of 5 μL), the ideal bilinear relationship between the peak current of the sensor and the concentration of catechol was achieved with a linear range of 0.1–200 μM for catechol. The detection limit was calculated as 0.03 μM (S/N = 3). The sensitivities were 42.5295 and 2.6199 μA·μM−1·cm−2, respectively. In addition, the sensor was successfully applied for the detection of catechol in tap water, river water, and tea samples.