Efficient, Reversible Lead Adsorption in a Thiol‐Decorated Zirconium‐Metal–Organic Framework

Why It Matters

The reversible, high‑capacity capture of Pb(II) offers a scalable, recyclable solution for heavy‑metal water remediation, addressing tightening environmental regulations and industrial demand.

Key Takeaways

• Thiol‑decorated Zr‑MOF captures Pb(II) efficiently.
• Mixed S/O chelation drives high adsorption capacity.
• 1 M HCl fully regenerates adsorbent for ten cycles.
• Effective on Pb‑perovskite solar cell leachate.
• Flexible DMSA linkers enable reversible binding.

Pulse Analysis

Metal‑organic frameworks (MOFs) have emerged as a versatile platform for selective metal capture because their pore chemistry can be tuned at the molecular level. The newly reported zirconium‑based MOF, Zr‑DMSA, incorporates meso‑2,3‑dimercaptosuccinic acid linkers that expose both thiol and carboxylate groups to the internal surface. This dual‑functionality creates high‑affinity sites for Pb(II) ions, delivering adsorption capacities that rival or exceed those of conventional sorbents while maintaining the structural integrity of the framework.

Solid‑state NMR, pair‑distribution function analysis, and X‑ray photoelectron spectroscopy reveal that Pb(II) binds through a mixed S/O chelation mechanism, leveraging the flexibility of the “dangling” ligands to accommodate the ion. Importantly, the binding is fully reversible; a simple 1 M HCl wash strips the lead from the thiol sites, restoring the original adsorption performance. The material sustains ten consecutive adsorption–desorption cycles with negligible loss of capacity, demonstrating robustness required for real‑world water‑treatment processes.

Beyond laboratory solutions, Zr‑DMSA proved effective in extracting lead leached from damaged perovskite solar cells, operating efficiently at both ambient and elevated temperatures. Its rapid regeneration and high selectivity position it as a promising candidate for industrial‑scale heavy‑metal remediation, where cost‑effective recyclability is a critical metric. As regulatory pressure on lead discharge intensifies, technologies that combine high uptake, easy regeneration, and chemical stability are likely to attract investment and accelerate deployment in municipal and industrial water‑purification systems.