A Novel Thin-Layer Flow Cell Sensor System Based on BDD Electrode for Heavy Metal Ion Detection.

Area of Science:

• Electrochemistry
• Environmental Science
• Analytical Chemistry

Background:

• Heavy metal contamination in water poses significant environmental and health risks.
• Accurate and efficient detection methods are crucial for monitoring water quality.
• Boron-doped diamond (BDD) electrodes offer unique advantages in electrochemical sensing due to their wide potential window and stability.

Purpose of the Study:

• To develop and validate an automated electrochemical sensor system for heavy metal ion determination.
• To utilize a thin-layer flow cell and BDD working electrode for enhanced detection efficiency.
• To assess the system's performance for on-site monitoring of zinc (Zn²⁺) and other heavy metals.

Main Methods:

• Fabrication of an electrochemical sensor incorporating a thin-layer flow cell and a BDD working electrode.
• Development of a fluidic automatic detection system for anodic stripping voltammetry.
• Optimization of electrodeposition parameters, including deposition time and reagent consumption.
• Validation using standard addition method in real water samples and simultaneous multi-ion detection.

Main Results:

• The system demonstrated high sensitivity and a low detection limit for Zn²⁺ (2.1 μg/L) within a linear range of 10–150 μg/L.
• Excellent repeatability was achieved with a relative standard deviation of 1.60% for repeated measurements.
• Successful application in real water samples with recoveries ranging from 92% to 118%.
• Capability for simultaneous detection of Zn²⁺, Cd²⁺, and Pb²⁺ was confirmed.

Conclusions:

• The developed automated electrochemical sensor system is highly effective for sensitive and repeatable heavy metal ion determination.
• The thin-layer flow cell and BDD electrode design improve electrodeposition efficiency and reduce reagent consumption.
• The system shows significant potential for practical on-site environmental monitoring of multiple heavy metal contaminants.