Surface modification of CuO nanoparticles with conducting polythiophene as a non-enzymatic amperometric sensor for sensitive and selective determination of hydrogen peroxide

The combination between conducting polymer and metal oxide semiconductor to fabricate novel nanocomposite is a straightforward route to formulate an effective electrochemical sensors. In this report, the catalytic efficiency of the polythiophene doped CuO (Pth-CuO) electro-catalyst was scrutinized as a non-enzymatic amperometric sensor for efficient determination of H2O2. The nanocomposite was synthesized by the oxidative polymerization of thiophene monomers followed by a simple ultra-sonication method. Several spectroscopic and microscopic tools were used for the systematic characterization of the as-synthesized nanocomposite. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) studies revealed that the Pth-CuO modified glassy carbon electrode (GCE) showed a higher catalytic efficiency compared with undoped CuO/GCE, pure Pth/GCE, or unmodified GCE. In the amperometric investigation, the Pth-CuO/GCE exhibits excellent sensitivity of 442.25 μAmM−1cm−2 with a wide dynamic response of 20 – 3300 μM and a low detection limit of 3.86 μM (S/N=3). The proposed sensor exhibits an excellent selectivity towards H2O2 in the existence of various interfering biomolecules. Furthermore, this modified sensor electrode exhibited good operational and storage stability, reproducibility and repeatability with an acceptable%RSD as well as suitable for real sample analysis. Such fabricated Pth-CuO nanocomposite signifies a tremendous electrocatalyst for the efficient sensing of H2O2.