Development of Palladium on Bismuth Sulfide Nanorods as a Bifunctional Nanomaterial for Efficient Electrochemical Detection and Photoreduction of Hg(II) Ions

A nanocomposite containing palladium nanoparticles embedded on bismuth sulfide nanorods (Pd@Bi 2 S 3 ) was synthesized based on a solvothermal method. The structural features, composition, and morphology were characterized by XRD, FT-IR, FE-SEM-EDS, FE-TEM, HAADF-STEM, XPS, N 2 physisorption, and UV–vis. Further electrochemical measurements by EIS, CV, DPV, and LSV techniques were done. It revealed that Pd@Bi 2 S 3 /GCE were exploited as electrochemical sensors for the detection of toxic mercuric ions (Hg 2+ ), which provides a wide linear range of 0.049–445 μM, excellent sensitivity of 1.17 μA μM –1 cm –2, and detection limit of 13.5 nM. The modified electrode has also been successfully applied for the detection of Hg 2+ in sea fish, river fish, and water samples. The Pd@Bi 2 S 3 /GCE signifies a robust, usability, and highly effective method for trace level detection of Hg 2+ ions. Furthermore, these Pd@Bi 2 S 3 bifunctional catalysts were discovered to have good photoreduction activity for Hg 2+ ions upon the visible-light irradiation.