A modified electrode using carboxylated multiwalled carbon nanotubes and 1-butyl-2,3-dimethylimidazolium hexafluorophosphate ionic liquid for a simultaneous hazardous textile dye sensor

Abstract

This research attempted to develop a simultaneous, sensitive and low-cost electrochemical sensor for acid blue 29 (AB 29) and mordant yellow 10 (MY 10) determination which are textile dye pollutants in industrial waste waters. Therefore, the first electrochemical sensor has been developed for their simultaneous determination by modifying a glassy carbon electrode (GCE) with a composite consisting of 1-butyl-2,3-dimethylimidazolium hexafluorophosphate ([bmmim]PF6) 98% as an ionic liquid (IL) and carboxylated multiwalled carbon nanotubes (CMWCNTs). Direct electrochemical oxidation of AB 29 and MY 10 at the modified electrode showed two peak currents that were significantly improved due to the presence of the ionic liquid–carboxylated multiwalled carbon nanotube-glassy carbon electrode (IL/CMWCNT-GCE). The electrochemical signals improved due to the optimization of different parameters affecting the sensitivity such as pH, electrode composition, scan rate, accumulation potential and time. Individual and simultaneous determinations were performed by differential pulse voltammetry (DPV) under optimum conditions. The linear dynamic ranges of 0.10–25 μmol L⁻¹, with a detection limit of 0.06 μmol L⁻¹ for AB 29, and 0.6–30 μmol L⁻¹, and a detection limit of 0.5 μmol L⁻¹ for MY 10, were achieved. Finally, the proposed modified electrochemical sensor was utilized for individually and simultaneously detecting AB 29 and MY 10 in wastewater samples.