Simultaneously Selective Detection of Trace Lead and Cadmium Ions by Bi-Modified Delaminated TiCT/GCE Sensor: Optimization, Performance and Mechanism Insights.

Lead (Pb) and cadmium (Cd) ions have serious negative impacts on human health and the ecological environment due to toxicity, persistence and nonbiodegradability. Among various trace Pb and Cd ions detection technologies, electrochemical analysis is considered as one of the most promising methods. The deposition of Bi nanoparticles on delaminated TiCT (DL-TiCT) develops a sensor with good conductivity and performance. Square wave anodic stripping voltammetry (SWASV) technology was applied to simultaneously deposit Bi on DL-TiCT/GCE and achieve the rapid detection of Pb and Cd ions. The Bi nanoparticles effectively improved the sensitivity of Bi/DL-TiCT/GCE sensors to detect Pb and Cd ions. The preparation conditions of the Bi/DL-TiCT/GCE were optimized, including DL-TiCT droplet amount, solution pH, Bi concentration, deposition time and deposition potential, to improve the detection ability. The Bi/DL-TiCT/GCE sensor has detection limits of 1.73 and 1.06 μg/L for Pb and Cd ions, respectively (S/N > 3). This electrochemical sensor is easy, sensitive and selective to apply in actual water samples for trace Pb and Cd ions detection.