Fabrication of novel redox-active poly (4,5-dihydro-1,3-thiazol-2-ylsulfanyl-3-methyl-1,2-benzenediol)-gold nanoparticles film on MWCNTs modified electrode: Application as the electrochemical sensor for the determination of hydrazine

• A novel conducting polymer was fabricated by manipulation of the monomer structure.
• Gold nanoparticles were embedded to the conducting polymer by simple physical adsorption method.
• Multi-walled carbon nanotubes were used as a support to prepare nanocomposite modified electrode.
• The modified electrode shows remarkable electrocatalytic activity towards hydrazine oxidation.

In this study, a hybrid nanocomposite consisting of a conducting polymer and gold nanoparticles (AuNPs) is fabricated on a multi-walled carbon nanotubes modified glassy carbon electrode (MWCNTs/GCE). First, dihydroxy-benzene derivative (4,5-dihydro-1,3-thiazol-2-ylsulfanyl-1,2-benzenediol) containing sulphur and nitrogen groups was electrochemically synthesized and used as a monomer. Then, a thin layer of conducting polymer is coated electrochemically on a MWCNTs/GCE and the effective parameters have been optimized. Afterward, the nano-sized AuNPs are embedded by physical adsorption from colloidal solution of AuNPs. The resultant nanocomposite modified electrode is characterized by electrochemical methods and transmission electron microscopy. Finally, the potential application of nanocomposite film modified electrode has been investigated for the electrocatalytic oxidation of hydrazine. The experimental results showed that the response of modified electrode is linear in the range of 2.0–350.0 μM with detection limit (S/N = 3) of 0.6 μM for hydrazine.