Regulating Host-Guest Interactions in a Mixed-Ligand Metal-Organic Framework for Short-Chain PFAS Detection.

Area of Science:

• Environmental Chemistry
• Materials Science
• Analytical Chemistry

Background:

• Per- and polyfluoroalkyl substances (PFAS) are ubiquitous environmental contaminants with significant human health risks.
• Short-chain PFAS pose detection challenges due to their amphiphilic nature and lack of inherent optical properties.

Purpose of the Study:

• To develop a high-performance luminescence sensor for selective detection of short-chain PFAS.
• To investigate the sensing mechanism and key structural factors for effective MOF-based sensing.

Main Methods:

• Synthesis of a functionalized metal-organic framework (MOF), UiO-66-0.8NH2.
• Utilizing fluorescence spectroscopy for sensitive and visual detection of perfluorohexanoic acid (PFHxA).
• Investigating host-guest interactions and synergistic effects of hydrophobic and electrostatic forces.

Main Results:

• UiO-66-0.8NH2 demonstrated a sensitive and visual "turn-on" fluorescence response to PFHxA in aqueous solutions.
• The MOF exhibited selective detection capabilities for PFHxA.
• Mechanism studies elucidated the role of pore structure and ligand ratio in host-guest interactions.

Conclusions:

• The developed MOF sensor provides a facile and rapid method for detecting PFAS in water.
• Tailoring MOF pore structure and ligand composition is crucial for effective sensing of short-chain PFAS.
• This work advances the development of MOF-based materials for environmental monitoring.