ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Determination of Cd²⁺ and Pb²⁺ by polyindole/Mn₂O₃ nanocomposite and polyindole/Mn₂O₃/polyaniline nanofibers modified glassy carbon electrode

Azar Yousefi, Hossein Aghaie, Masoud Giahi, and Laleh Maleknia

Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran

E-mail: a.azaryousefi@yahoo.com

Received: 19 February 2022  Accepted: 22 June 2022

Abstract:

In this paper, the surface of the glassy carbon electrode was modified by polyindole (PIN)/Mn₂O₃ nanocomposite and PIN/Mn₂O₃/polyaniline (PANI) nanofibers and electrochemical behavior toward the sensing of Cd²⁺ and Pb²⁺ was investigated using differential pulse anodic stripping voltammetry. The amount of (PIN)/Mn₂O₃ nanocomposite was varied to find the best performance. In addition, cyclic voltammetry of ferrocyanide was used to describe the behavior of modified electrodes and the diffusion coefficient for PIN/Mn₂O₃ and PIN/Mn₂O₃/PANI samples containing 5%w/w (PIN)/Mn₂O₃ nanocomposite was 8.05 × 10^–7 and 1.29 × 10^–6 cm² s⁻¹, respectively. The synergistic effect of PANI and PIN/Mn₂O₃ in nanofibers structure enhances the accumulation efficiency and the charge transfer rate of metal ions. Under the optimal conditions, PIN/Mn₂O₃/PANI nanofibers modified electrode showed good linear relationships for Cd²⁺ and Pb²⁺ in a range of 0.05–450 µg L⁻¹, with the detection limit of 0.05 and 0.02 µg L⁻¹ for Pb²⁺ and Cd²⁺, respectively. The linear range and detection limit for PIN/Mn₂O₃ nanocomposite modified electrode was 1–200 µg L⁻¹and 9.85 and 10.72 µg L⁻¹ for Cd²⁺ and Pb²⁺, respectively.

Keywords: Heavy metal ions; Polyaniline; Differential pulse anodic stripping voltammetry; Polyindole

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-022-02343-5

Chemical Papers 77 (2) 733–743 (2023)