Simultaneous detection of hydroquinone and catechol by Cu/Bi-MOF-derived Cu/Bi@C nanocomposites

Abstract

Electrochemical detection techniques are unable to accurately distinguish isomers with similar structures and properties due to the poor stability and selectivity of some sensors and their susceptibility to environmental interference. Bimetallic synergistically synthesized MOF materials have various types of highly ordered pores and can be used as adsorbent materials and catalyst carriers. Therefore, a composite material was developed to prepare its derivative Cu/Bi@C using a bimetallic organic skeleton (Cu/Bi-MOF) as a precursor, inheriting the large number of active sites on the surface of the MOF and large surface area, while improving the electrochemical response signal. The morphology and structure of the synthesized Cu/Bi@C composites were tested and analyzed by XRD, SEM and other characterization methods, and the electrochemical response of the Cu/Bi@C nanocomposites was analyzed by using an electrochemical workstation. In this study, a simple and highly selective electrochemical method was developed for the simultaneous determination of catechol and catechol quinone. Differential pulse voltammetry (DPV) was used for the simultaneous detection of HQ and CC. The results showed that the Cu/Bi@C electrode was able to efficiently and highly selectively detect both isomers. The Cu/Bi@C electrode could detect HQ and CC in the range of 2–600 μM and 2–800 μM, respectively, under the detection environment of pH = 6.0. The detection limits were 0.08 μM and 0.11 μM (S/N = 3), respectively. The sensor was successfully applied to real samples and showed low detection limits, good recoveries, high selectivity, stability and reproducibility. This provides a new idea for electrochemical detection and is expected to be applied in several fields.