Ratiometric Fluorescent Probe with Metal-Mediated Dual-Emission Centers for Ultrasensitive and Interference-Resistant...

Area of Science:

• Materials Science
• Analytical Chemistry
• Environmental Monitoring

Background:

• Sulfur hexafluoride (SF₆) is a potent greenhouse gas widely used in electrical grid insulation.
• Effective monitoring of SF₆ leaks is critical for environmental protection and grid reliability.
• Existing SF₆ detection methods often lack the required sensitivity, selectivity, or resistance to interference.

Purpose of the Study:

• To develop a novel, convenient, efficient, and interference-resistant method for SF₆ detection.
• To design a ratiometric fluorescent probe capable of highly sensitive and selective SF₆ sensing.
• To validate the probe's performance for practical SF₆ leakage monitoring in grid insulation systems.

Main Methods:

• Synthesis of a dual-emission ratiometric fluorescent probe (NiCDs@MOF) by anchoring nickel-containing carbon dots (NiCDs) within a nickel-based metal-organic framework (MOF).
• Investigation of the probe's SF₆ recognition and capture mechanism via multisite interactions and interfacial charge transfer.
• Evaluation of the probe's sensitivity, selectivity, anti-interference capability, reusability, and photostability for SF₆ detection.

Main Results:

• The NiCDs@MOF probe exhibited efficient recognition and capture of SF₆ molecules, triggering distinct ratiometric fluorescence changes.
• Achieved an ultralow SF₆ detection limit of 2.8 ppb within 3 minutes with excellent selectivity.
• Demonstrated robust anti-interference capabilities against common interfering gases, high reusability (RSD < 2.7%), and photostability (fluorescence fluctuation <5%).

Conclusions:

• The developed ratiometric fluorescent probe provides a highly sensitive, selective, and robust platform for SF₆ gas leak detection.
• The NiCDs@MOF probe offers a promising and innovative solution for effective monitoring of SF₆ in electrical grid insulation systems.
• The probe's convenient and efficient nature, coupled with its anti-interference properties, addresses key challenges in current SF₆ monitoring technologies.