Electrochemical sensor for detection of mercury (II) ions in water using nanostructured bismuth hexagons

This study presents a systematic observation of the ability of bismuth nanostructures to detect trace amounts of mercury. Nanostructured hexagons of bismuth were synthesized using electrochemical deposition with potentiostatic mode on indium tin oxide-coated glass electrodes. Regular hexagons composed of nano-sized hexagonal building blocks ( edge length approximate to 80 to 700 nm) with well-defined edges were observed in scanning electron microscopy studies. X-ray diffraction pattern indicates the presence of polycrystalline bismuth and bismuth oxide in rhombohedral and cubic phases, respectively. X-ray photoelectron spectroscopy was done to analyze the chemical structure of the prepared nanostructures. Square wave anodic stripping voltammetry technique confirms that these nanostructured electrodes are highly sensitive to Hg2+ ions down to concentrations as low as 0.74 ppb.