A Review of Quartz Crystal Microbalance-Based Mercury Detection: Principles, Performance, and On-Site Applications

Area of Science:

• Environmental Science
• Analytical Chemistry
• Materials Science

Background:

• Mercury (Hg) is a significant global toxicant, prompting international action like the Minamata Convention.
• Ongoing global initiatives aim to reduce mercury emissions and monitor its environmental presence.
• Accurate and accessible mercury monitoring tools are crucial for environmental and occupational safety.

Purpose of the Study:

• To develop a simple, rapid, and sensitive mercury detection device.
• To evaluate the performance of a quartz crystal microbalance (QCM-Hg) sensor for mercury monitoring.
• To explore the potential of the QCM-Hg system for both air and aqueous sample analysis.

Main Methods:

• Development of a QCM-Hg sensor utilizing the amalgamation reaction between mercury and a gold electrode.
• Experimental validation of the sensor's response to varying mercury concentrations and environmental conditions.
• Integration of a reduction-vaporization method for detecting mercury in aqueous samples.

Main Results:

• A direct proportional relationship was observed between mercury concentration and the QCM-Hg sensor's oscillation frequency shift.
• Detection sensitivity was enhanced by increasing flow rates and measurement durations.
• A detection limit of approximately 1 µg/m³ was achieved for airborne mercury, comparable to commercial analyzers.
• The system demonstrated potential for detecting mercury in aqueous samples down to approximately 0.05 µg/L.

Conclusions:

• The developed QCM-Hg sensor system is a promising tool for on-site mercury monitoring in various environmental and occupational settings.
• Its simplicity, rapidity, and sensitivity make it a viable next-generation mercury detection technology.
• The QCM-Hg sensor contributes to global efforts in managing mercury risks and environmental protection.