Sensitive Lead Detection Through Integration of Electrochemical Deposition and Graphene Ion-Sensitive Field-Effect Transistor

A highly sensitive lead ion sensor is developed using graphene ion-sensitive field-effect transistors (G-ISFETs) in an aqueous environmental setting. The sensing channel employs monolayer graphene, while a PVC membrane, incorporating a lead ionophore, serves as the ion-sensitive membrane. The sensor utilizes an electrochemical deposition technique to preconcentrate Pb ion concentration at the solution-sensor interface to enable detection at ultra-low concentration. Notably, the integrated sensor exhibits an exceptional sensitivity of - 36.7 mV/decade and achieves an ultra-low detection limit of 5.6x10
^-4
ppt, with a limit of quantitation (LOQ) set at 1.0x10
^-3
ppt.