The Electrochemical Oxidation of Hydroquinone and Catechol through a Novel Poly-geminal Dicationic Ionic Liquid (PGDIL)-TiO2 Composite Film Electrode

Yanni Guo; Deliang He; Aomei Xie; Wei Qu; Yining Tang; Lei Zhou; Rilong Zhu

doi:10.3390/polym11111907

The Electrochemical Oxidation of Hydroquinone and Catechol through a Novel Poly-geminal Dicationic Ionic Liquid (PGDIL)-TiO₂ Composite Film Electrode

Polymers (Basel). 2019 Nov 19;11(11):1907. doi: 10.3390/polym11111907.

Authors

Yanni Guo¹, Deliang He¹, Aomei Xie², Wei Qu¹, Yining Tang¹, Lei Zhou¹, Rilong Zhu¹

Affiliations

¹ State key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Applied Chemistry, Changsha 410082, China.
² College of Marxism, Jishou University, Jishou 416000, China.

Abstract

A novel poly-geminal dicationic ionic liquid (PGDIL)-TiO₂/Au composite film electrode was successfully prepared by electrochemical polymerization of 1,4-bis(3-(m-aminobenzyl)imidazol-1-yl)butane bis(hexafluorinephosphate) containing polymerizable anilino groups in the electrolyte containing nano-TiO₂. The basic properties of PGDIL-TiO₂/Au composite films were studied by SEM, cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry. The SEM results revealed that the PGDIL-TiO₂ powder has a more uniform and smaller particle size than the PGDIL. The cyclic voltammetry results showed that the catalytic effect on electrochemical oxidation of hydroquinone and catechol of the PGDIL-TiO₂ electrode is the best, yet the R_ct of PGDIL-TiO₂ electrode is higher than that of PGDIL and TiO₂ electrode, which is caused by the synergistic effect between TiO₂ and PGDIL. The PGDIL-TiO₂/Au composite electrode presents a good enhancement effect on the reversible electrochemical oxidation of hydroquinone and catechol, and differential pulse voltammetry tests of the hydroquinone and catechol in a certain concentration range revealed that the PGDIL-TiO₂/Au electrode enables a high sensitivity to the differentiation and detection of hydroquinone and catechol. Furthermore, the electrochemical catalytic mechanism of the PGDIL-TiO₂/Au electrode was studied. It was found that the recombination of TiO₂ improved the reversibility and activity of the PGDIL-TiO₂/Au electrode for the electrocatalytic reaction of HQ and CC. The PGDIL-TiO₂/Au electrode is also expected to be used for catalytic oxidation and detection of other organic pollutants containing -OH groups.

Keywords: catechol; hydroquinone; nano-TiO2; poly-geminal dicationic ionic liquid.