Electrochemical detection of hydroquinone and catechol with covalent organic framework modified carbon paste electrode

A covalent organic framework (COF) modified carbon paste electrode (CPE) was used for the electrochemical detection of hazardous hydroquinone (HQ) and catechol (CC). Due to the advantages of TpBD-COF (large surface area, abundant functional groups and high chemical stability), rapid quantitative determination of HQ and CC was accomplished by differential pulse voltammetry (DPV). Under the optimal conditions, the resultant sensor showed an extended linear response range for HQ and CC (1-2000 mu mol L-1), and the detection limits were 0.31 and 0.46 mu mol L-1 (S/N = 3) respectively. The simultaneous determination of HQ and CC can be accomplished by data deconvolution. In binary solutions with one constant constituent concentration, a linear relationship was established between the deconvoluted peak current and concentration of the changing constituent. In addition, the electrochemical sensor showed strong anti-interference ability, good reproducibility (a relative standard deviation of 0.99% for HQ and 0.77% for CC, n = 5) and applicability in real sample detection (with spiking recoveries from 97.7%- 101.6% for HQ and 100.3% - 103.3% for CC). These results demonstrate that COF modified carbon materials are promising candidates for efficient electrochemical detection of phenolic compounds.