Dual-functional metal-organic frameworks-based hydrogel micromotor for uranium detection and removal

Area of Science:

• Materials Science
• Environmental Science
• Nanotechnology

Background:

• Self-propelled micro/nanomotors show promise for environmental remediation.
• Radioactive waste detection and removal using micromotors remains an underexplored area.
• Engineered micromotors capable of rapid detection and high adsorption are needed for radioactive waste management.

Purpose of the Study:

• To design and synthesize self-propelled micromotors for efficient uranium detection and removal.
• To investigate the performance of zeolite imidazolate framework (ZIF-8)-hydrogel composite micromotors.
• To explore the potential of magnetic nanoparticles for micromotor actuation and recovery.

Main Methods:

• Inverse emulsion polymerization was used to create ZIF-8-hydrogel composite micromotors.
• Magnetic ferroferric oxide nanoparticles were incorporated for magnetic control and swarm formation.
• Density functional theory (DFT) calculations were performed to understand uranyl ion binding.
• Fluorescence quenching was utilized for uranium detection.

Main Results:

• The micromotors demonstrated high uranium adsorption capacity (747.3 mg g⁻¹).
• Fast and sensitive uranium detection was achieved via fluorescence quenching with a low detection limit of 250 ppb.
• Magnetic nanoparticles enabled efficient recycling and controlled movement, including swarm formation.
• DFT calculations confirmed strong binding interactions between carboxyl groups and uranyl ions.

Conclusions:

• Self-propelled ZIF-8-hydrogel micromotors offer a novel strategy for radioactive wastewater remediation.
• The integration of magnetic nanoparticles enhances micromotor functionality for detection and removal.
• These smart materials provide a promising approach for efficient uranium management.