Development of boron doped diamond electrodes material for heavy metal ion sensor with high sensitivity and durability

We report on the optimized substrate pretreatment and deposition process conditions for boron-doped diamond (BDD) electrodes fabricated by hot-filament chemical vapor deposition (HFCVD). The optimized BDD electrode with a doping concentration of 8000 ppm showed high accuracy and precision in detecting Cd(II), Pb(II), and Cu(II) ions. In addition, this demonstrates excellent selectivity against external metal ions under the optimized stripping voltammetry measurement conditions. The detection limits of the target ions of Cd(II), Pb(II), and Cu(II) were 0.55 (±0.05), 0.43 (±0.04), and 0.74 (±0.06) μg/L (S/N = 3), respectively. In real samples spiked with 100 μg/L Cd(II), Pb(II), and Cu(II), both the accuracy and precision of the BDD electrode were within 5%; the interference with organic matter was also negligible. The excellent selectivity and long-term stability indicate that the BDD electrode developed in this study are potentially useful for online water environment monitoring systems. •Deposition conditions for a boron doped diamond (BDD) and the measurement conditions for differential-pulse anodic stripping voltammetry were optimized.•Optimized BDD sensors possesses wide linear sensitivity range and low detection limit for three different heavy metal ions (Cu(II), Cd(II), and Pb(II)).•Optimized BDD sensors exhibits excellent selectivity and repeatability toward the real sample analysis with negligible interference effects from various heavy metal ions.•Long-term stability is demonstrated through repeated long-term test using optimized BDD sensors.