Electrochemical sensor based on UiO-66-NH2/COCl-MWCNT/CB for simultaneous detection of dihydroxybenzene isomers in different water samples

In this study, metal–organic backbone (UiO-66-NH 2 ) and thionyl chloride functionalized carbon nanotubes (COCl-MWCNT) were successfully synthesized, and introduced into carbon black (CB) for fabricating novel electrochemical sensor UiO-66-NH 2 /COCl-MWCNT/CB/GCE towards simultaneous determination of dihydroxybenzene isomers hydroquinone (HQ), catechol (CC) and resorcinol (RC). Due to large surface area, excellent conductivity, good electrocatalytic activity and high stability the developed composite modified electrode delivered excellent analytical performance for these three analytes. Under optimal conditions, differential pulse voltammetric (DPV) currents showed good linear relationships with the concentrations of HQ, CC and RC with low detection limits (0.24 μM, 0.11 μM, 0.47 μM) and wide detection ranges (1–1000 μM and 5–1000 μM). In addition, this sensor demonstrated favorable reproducibility, stability and good selectivity for HQ, CC and RC and possessed a great potential for selective detection of dihydroxybenzene isomers   in environmental water samples.