A Selective and Sensitive Sensor for Determination of Sulfide in Aquatic Environment

A cost-effective, sensitive, and selective electrochemical sensor for the analysis of sulfide based on the high affinity of sulfide to metallic silver is proposed. To achieve high sensitivity while lowering the cost of the sensor, silver nanoparticles (Ag NPs), which possess larger metal surface area-to-volume ratio compared with bulk silver, were employed for the development of the sensor. The sensor was prepared through electrodeposition of Ag NPs on the surface of a carbon ionic liquid electrode using potentiostatic double-pulse technique, and it showed a wide linear range from 25 to 2500 $\mu $ M of sulfide with a detection limit of 6.02 $\mu $ M. Since the analysis of sulfide was performed at a remarkably low detection potential, the presented sensor offered high selectivity against common interferents and was successfully applied to the analysis of sulfide in a hot spring water sample.