Interfacial Coordinational Bond Triggered Photoreduction Membrane for Continuous Light-Driven Precious Metals...

Area of Science:

• Materials Science
• Environmental Chemistry
• Nanotechnology

Background:

• Traditional precious metal recovery relies heavily on chemical or electric energy, which is not sustainable.
• Developing renewable energy-driven methods for selective precious metal recycling is essential for achieving carbon neutrality.
• Interfacial engineering offers a promising route to design advanced materials for resource recovery.

Purpose of the Study:

• To develop a novel material for the selective recovery of precious metals (PMs) using renewable energy.
• To engineer an interfacial structure by covalently integrating pyridine groups onto a photoactive semiconductor (SnS2) to create Py-SnS2.
• To demonstrate the efficiency of Py-SnS2 in capturing and recovering Au3+, Pd4+, and Pt4+.

Main Methods:

• Covalent integration of coordinational-active pyridine groups onto the surface of photoactive SnS2 to form Py-SnS2.
• Utilizing the combined effects of coordinational binding and SnS2 photoreduction for selective PM capture.
• Fabricating a Py-SnS2 membrane and integrating it into a light-driven flow cell for continuous precious metal recovery.

Main Results:

• Py-SnS2 exhibited significantly enhanced selective capturing performance for Au3+, Pd4+, and Pt4+.
• Achieved high recycling capacities: 1769.84 mg/g for Au3+, 1103.72 mg/g for Pd4+, and 617.61 mg/g for Pt4+.
• Demonstrated a 96.3% recovery efficiency for continuous gold recycling from CPU leachate using a light-driven flow cell.

Conclusions:

• A novel strategy for fabricating coordinational bond-triggered photoreductive membranes for continuous precious metal recovery was reported.
• The Py-SnS2 material shows great potential for sustainable precious metal recycling, contributing to a circular economy.
• This approach can be extended to other photocatalysts for broader environmental applications, supporting green chemistry initiatives.