Simple potentiometry and cyclic voltammetry techniques for sensing Hg ions in water using a promising flower-shaped WS-WO/poly-2-aminobenzene-1-thiol nanocomposite thin film electrode.

A highly promising flower-shaped WS-WO/poly-2-aminobenzene-1-thiol (P2ABT) nanocomposite was successfully synthesized a reaction involving 2-aminobenzene-1-thiol, NaWO, and KSO as oxidants. The WS-WO/P2ABT nanocomposite demonstrated remarkable potential as a sensor for detecting harmful Hg ions in aqueous solutions. The sensing behavior was evaluated over a wide concentration range, from 10 to 10 M, using a simple potentiometric study on a two-electrode cell. The calibration curve yielded an excellent Nernstian slope of 33.0 mV decade. To further validate the sensing capabilities, cyclic voltammetry was employed, and the results showed an increasing trend in the cyclic voltammetry curve as the Hg concentration increased from 10 to 10 M with an evaluated sensitivity of 2.4 μA M. The WS-WO/P2ABT nanocomposite sensor exhibited exceptional selectivity for detecting Hg ions, as no significant effects were observed from other interfering ions such as Zn, Ni, Ca, Mg, Al, and K ions in the cyclic voltammetry tests. Furthermore, the sensor was tested on a natural sample that was free of Hg ions, and the cyclic voltammetry curves did not produce any characteristic peaks, confirming the sensor's specificity for Hg detection. The sensor's cost-effectiveness and ease of fabrication present the potential for developing a simple and practical sensor for detecting highly poisonous ions in aqueous solutions.