Ultrasensitive electrochemical sensor for simultaneous determination of cadmium and lead ions based on one-step co-electropolymerization strategy

Abstract

A convenient and novel electrochemical strategy for simultaneous detection of cadmium ion (Cd2+) and lead ion (Pb2+) was established in this work. Well identifiable stripping peaks for Cd2+ and Pb2+ were achieved based on a three-dimensional nanoporous silica incorporated with polyfurfural modified glassy carbon electrode (GCE) by one-step co-electropolymerization. The polyfurfural was merged into nanoporous silica in order to enhance the sensor performance through improving the electrode surface area, supplying more binding sites for coordinating with metal ions. The prepared sensor exhibits more excellent electroactive surface area and excellent analytical properties than those just polyfurfural film modified GCE or just nanoporous silica on GCE. Comparing the traditional method, the proposed strategy displays high stability, reliability, favorable sensitivity, and outstanding selectivity for the simultaneous detecting Cd2+ and Pb2+. Impressively, this proposed strategy possessed a wide linear range of 1.5 ng/L to 6200 μg/L and a low limit of detection (LOD) of 0.9 ng/L (S/N = 3) for Cd2+, while linear response range with 0.05 ng/L to 5200 μg/L and LOD of 0.02 ng/L (S/N = 3) for Pb2+. In particular, the fabricated sensor had splendid analytical performance for detection of target ions in potable water, and satisfactory results have been obtained in practice.