A sensitive electrochemical sensor for simultaneous voltammetric sensing of cadmium and lead based on Fe3O4/multiwalled carbon nanotube/laser scribed graphene composites functionalized with chitosan modified electrode

In this work, based on a Fe 3 O 4 /multiwalled carbon nanotube/laser scribed graphene composites functionalized with chitosan modified glassy carbon electrode (Fe 3 O 4 /MWCNTs/LSG/CS/GCE), a highly active, sensitive, facile and low-cost electrochemical sensor was fabricated to determine cadmium (Cd 2+ ) and lead (Pb 2+ ) simultaneously using square wave anodic stripping voltammetry (SWASV). This novel nanocomposite possessed a significantly large specific area, remarkably high conductivity and excellent absorption ability. By in situ plating bismuth film, this constructed sensor proved favorable electrochemical response with a wide linear range from 1 to 200 μg L −1 , and an ultralow detection limit of 0.1 and 0.07 μg L −1 for Cd 2+ and Pb 2+ (S/N = 3), respectively. Furthermore, excellent repeatability, reproducibility, stability, and reliable practical applicability were achieved in the constructed sensor. Finally, the prepared sensor is believed to provide promising applications in the electrochemical determination of heavy metal ions .