Novel determination of Cd and Zn in soil extract by sequential application of bismuth and gallium thin films at a modified screen-printed carbon electrode

This study describes a novel electrochemical technique for the detection of bioavailable cadmium(II) (Cd) and zinc(II) (Zn), in real soil samples. This was made possible by the sequential deposition of bismuth and gallium thin films on modified screen-printed carbon electrodes (SPEs). A range of graphitic modifications were evaluated, and a reduced graphene oxide/graphitic carbon nitride (RGO/g-C3N4) modification proved most suitable. Electrochemical characterisation demonstrated superior stability, attributed to the functional groups of GO, and an increased electron transfer rate, attributed to the intercalated g-C3N4.