Synthesis and characterization of benzenesulfonate derivatives doped poly(3,4-ethylenedioxythiophene) films and their application in electrocatalysis

摘要

The dopant anion in poly(3,4-ethylenedioxythiophene) (PEDOT) plays a critical role in determining the physical and chemical properties of these conducting polymers. In this paper, six kinds of benzenesulfonate derivatives, including benzenesulfonate (BS), p-methylbenzene-sulfonate (p-MBS), p-aminobenzenesulfonate (p-ABS), p-hydroxybenzene-sulfonate (p-HBS), m-carboxylbenzenesulfonate (m-CBS) and m-nitrobenzenesulfonate (m-NBS) were used to dope PEDOT via a facile electrochemical deposition strategy. The presence of the dopants in the conducting polymer matrix was verified by Fourier transform infrared spectroscopy (FTIR) and ultraviolet spectrum (UV/vis) and the morphologies of the resulting benzenesulfonate derivatives doped PEDOT films were analyzed by scanning electron microscopy (SEM). The electrocatalytic activities of these doped PEDOT films toward VB_2, VBg and VC were investigated by cyclic voltammetry (CV). Among them, the PEDOT/p-ABS~- film shows a higher catalytic peak currents, which might be ascribed to the large surface area of nanostructured PEDOT/p-ABS~- film, and the strong interaction between —NH— group doped in PEDOT/p-ABS~- film and VB_2, VBg and VC via hydrogen bonding. Then the PEDOT/p-ABS~- film modified glass carbon electrode (PEDOT/p-ABS~-/GCE) was utilized as an electrochemical sensor for the simultaneous detection of these vitamins, and the linear ranges for VB_2, VBg and VC are 0.05-200 μM, 0.5-1000 μM and 1-1500 μM with limits of detection of 0.015 μM, 0.12 μM and 0.46 μM, respectively, (S/N = 3). Moreover, the modified electrode was successfully employed for the determination of VB_2, VBg and VC in human blood plasma with satisfactory results.