Hossein Khosropour, Behzad Rezaei, Ali A. Ensafi

A B S T R A C T
Hazardous dyes are unleashed in water systems from different industries that these materials have trouble with health and environmental balance. Therefore, this research expands a selective sensor for determining residual hazardous textile dyes in wastewaters. A novel electrochemical sensor based on RuO2/reduced graphene oxide/ carboxylated multiwalled carbon nanotubes (RuO2/rGO/CMWCNTs) modified glassy carbon electrode was developed for simultaneous determination of acid blue 40 (AB 40) and acid blue 29 (AB 29). The morphology and structure of the RuO2/rGO/CMWCNTs were investigated by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS) and Fourier transform infrared spectroscopy (FT-IR). The properties of several parameters affecting the sensitivity of the determination of both species, such as scan rate, accumulation time, accumulation potential and pH were investigated. The electrochemical behavior of these species was investigated using square wave voltammetry (SWV) under the optimized condition. Linear dynamic ranges for AB 40 and AB 29 determination were 0.05–50.0 μmol L−1 and 0.5–75.0 μmol L−1 with the detection limits of 0.01 and 0.1 μmol L−1, respectively. Finally, the applicability of the electrochemical sensor was verified by the real wastewater samples analysis.

Keywords:
Simultaneous determination, Acid blue 40, Acid blue 29, Reduced graphene oxide, Multiwall carbon nanotubes