Fabrication of Boron-Doped Diamond Film Electrode for Detecting Trace Lead Content in Drinking Water

This work aimed to fabricate a boron-doped diamond film electrode for detecting trace amounts of lead in drinking water so as to safeguard it for the public. Available detectors suffer from high costs and complex analytical processes, and commonly used electrodes for electrochemical detectors are subject to a short life, poor stability, and secondary pollution during usage. In this work, a boron-doped diamond (BDD) electrode was prepared on a porous titanium substrate, and the microstructure and electrochemical properties of the BDD electrode were systematically studied. Moreover, the stripping parameters were optimized to obtain a better signal response and determine the detection index. As a result, diamond particles were closely arranged on the surface of the BDD electrode with good phase quality. The electrode showed high electrochemical activity, specific surface area, and low charge transfer resistance, which can accelerate the stripping reaction process of Pb²⁺. The BDD electrode presented a low detection limit of 2.62 ppb for Pb²⁺ under an optimized parameter set with an enrichment time of 150 s and a scanning frequency of 50 Hz. The BDD electrode also has good anti-interference ability. The designed BDD electrode is expected to offer a reliable solution for the dilemma of the availability of metal electrodes and exhibits a good application prospect in the trace monitoring of Pb²⁺ content in drinking water.