▎ 摘　　要

In this work, based on a Fe3O4/multiwalled carbon nanotube/laser scribed graphene composites functionalized with chitosan modified glassy carbon electrode (Fe3O4/MWCNTs/LSG/CS/GCE), a highly active, sensitive, facile and low-cost electrochemical sensor was fabricated to determine cadmium (Cd2+) and lead (Pb2+) 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 mu g L-1, and an ultralow detection limit of 0.1 and 0.07 mu g L-1 for Cd2+ and Pb2+ (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.