Potentiometric determination of Pb²⁺ ions using hybrid assembly of zinc oxide@polyaniline nanocomposites

ABSTRACT

Over the recent years, the detection and determination of level of pollutant in environment have become indispensable. This allows for the adoption of various methods to evade the pollution caused by these toxicant entities. This has enhanced the interest of researchers to develop sustainable sensors to determine the trace level concentration of harmful target species. Although the list of these pollutants is undoubtedly too long, toxic metal ions, like Pb²⁺ ions beyond certain limit, can severely endanger the whole ecosystem. Therefore, the present study is dedicated toward the development of Pb²⁺ ion-selective electrode based on the membrane of zinc oxide/polyaniline nanocomposites. Nanocomposite assembly was synthesized using in-situ chemical oxidative polymerization method and characterized using spectroscopic techniques, such as energy‐dispersive spectroscopy, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, dynamic light scattering, etc. The proposed potentiometric sensor exhibits excellent selectivity toward Pb²⁺ ions with detection limit of 2.239 × 10⁻⁶ M, Nernstian slope of 23.31 ± 2.5 mV decade⁻¹ and a wide linear concentration range of 1.0 × 10⁻⁵ M to 1.0 × 10⁻¹ M. Moreover, the designed Pb²⁺ ion-selective electrode was successfully examined for its practical applicability in Pb²⁺−EDTA complexometric titration as well as potentiometric determination of concentration of Pb²⁺ ions in real-life samples.

GRAPHICAL ABSTRACT

KEYWORDS:

• Electrochemical sensor
• ion-selective electrode
• lead ions
• nanocomposites
• potentiometry

Acknowledgment

The authors are thankful to UGC for awarding National Fellowship for OBC Candidate (student id- 201819-NFO-2018-19-OBC-PUN-78836) to Miss Gagandeep Kaur.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

Gagandeep Kaur: Investigation, Writing-Original draft; Harpreet Kaur: Supervision, Conceptualization, Methodology, Resources, Project administration, Writing-review and editing; Susheel K. Mittal: Methodology, Writing-review and editing.

Additional information

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Notes on contributors

Gagandeep Kaur

Miss. Gagandeep Kaur received her M.Sc. (2017) from Department of Chemistry, Punjabi University, Patiala, India. She is Research Scholar. Her h-index from Google scholar citations is 2. Her fields of research interest are nanosynthesis, surface chemistry, sensors and environmental chemistry.

Harpreet Kaur

Dr. Harpreet Kaur received her Ph.D. degree (2006) from Department of Chemistry, Punjabi University, Patiala. She has been working as Senior Assistant Professor in Department of Chemistry, Punjabi University, Patiala, India. Her fields of research interest are Synthetic electrochemistry, surface chemistry, nanosynthesis and environmental chemistry. Her h-index from Google scholar citations is 11. She has more than 35 research papers in various reputed national and international journals.

Susheel K. Mittal

Prof. (Dr.) Susheel K. Mittal received his Ph.D. degree (1986) from Department of Chemistry, Guru Nanak Dev University, Amritsar, Punjab, India. He completed his Post-Doc (1986 – 1988) at Guru Nanak Dev University, Amritsar, Punjab, India. He has been working as Vice Chancellor, IK Gujral Punjab Technical University, Kapurthala, Punjab, India. His fields of interest are Chemical Sensors, Inorganic ion-exchange materials, Environmental chemistry biomedical waste management, etc. His h-index from Google scholar citations is 25. He has numerous research papers in various reputed national and international journals.