Simultaneous voltammetric determination of dihydroxybenzene isomers at single-walled carbon nanohorn modified glassy carbon electrode

摘要

The voltammetric behaviors of dihydroxybenzene isomers were studied at the single-walled carbon nanohorn modified glassy carbon (SWCNH-modified GC) electrode. Compared with the bare electrode, SWCNH-modified GC electrode has stronger electrocatalytic activity for the oxidation of dihydroxy-benzenes with the increase in peak current and the decrease in peak separation (△E_p) between the anodic and cathodic peaks. Furthermore, the three isomers can be determined simultaneously and sensitively by using linear sweep voltammetry at the SWCNH-modified GC electrode. For hydroquinone, catechol, and resorcinol, the oxidation peak currents are linear with the concentrations in the range of 0.5-100 μM, 0.5-100 μM, and 1.0-100 μM, respectively. Their detection limits at a signal-to-noise ratio of 3 are 0.1 μM, 0.2 μM, and 0.5 μM, respectively. These results make SWCNH-modified GC electrode a promising candidate for the simultaneous determination of isomers.