Cadmium(II)-selective potentiometric sensor based on synthesised (E)-2-benzylidenehydrazinecarbothioamide for the determination of Cd²⁺ in different environmental samples

ABSTRACT

In the present study, we developed a cadmium(II)-selective sensor using a novel poly(vinyl chloride) membrane, containing synthesised (E)-2-benzylidenehydrazinecarbothioamide as an ionophore. This newly developed cadmium(II)-selective sensor exhibits best performance with a membrane composition of poly(vinyl chloride) (PVC), bis(2-ethylhexyl) adipate (DEHA), ionophore, potassium tetrakis (p-chlorophenyl) borate (KTpClPB) at 32.0:63.0:4.0:1.0 ratio (%, w/w). The cadmium(II)-selective sensor exhibits a lower detection limit of 1.77 × 10⁻⁶ mol L⁻¹. This potentiometric sensor displays a stable potential response in the pH range of 5.0–10.0 and it shows a good selectivity for Cd²⁺ in the presence of interfering ions. The developed sensor shows a relatively fast response time (10 s), good reusability and stability. The proposed cadmium(II)-selective sensor was successfully applied as an indicator electrode in potentiometric titration of Cd²⁺ ions with EDTA and for the direct determination of Cd²⁺ ions in different environmental samples and in a waste battery sample.

KEYWORDS:

• Cadmium(II)
• ion-selective electrode
• environmental monitoring
• heavy metal analysis

Acknowledgments

The authors would like to thank Kamil Mert Yigit for his contributions.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Scientific Research Projects Commission of Tokat Gaziosmanpasa University (Project Number: 2019/54).