Environmental remediation using metal-organic frameworks: Recent progress in adsorption capacities, mechanisms, and practical applications

Abstract

Urgent global demand for sustainable environmental remediation solutions drives the development of advanced technologies. Toxic gases (CO_x, NO_x, SO_x, H₂S, NH₃), VOCs, and water contaminants (heavy metals, pharmaceuticals, dyes, pathogens) pose severe threats. Metal-organic frameworks (MOFs), with tunable porosity and multifunctionality, are revolutionary materials excelling in adsorption, catalysis, gas storage, and sensing for pollution mitigation. This review highlights cutting-edge MOF advancements, covering novel synthesis, enhanced properties, and scalable air/water purification applications. For CO₂ capture, Mg₂(dobpdc) and Co₂(dobdc) achieve 6.42 mmol g⁻¹ and 6.90 mmol g⁻¹ at 1 bar, 25 °C. Harmful gas adsorption excels with Cu₂Cl₂BBTA for NH₃ (19.79 mmol g⁻¹), MIL-101(Cr)-4F(1 %) for SO₂ (18.4 mmol g⁻¹), and MIL-101 for H₂S (38.4 mmol g⁻¹ at 20 bar). MOF-5 dominates VOC removal (1367 mg g⁻¹ trichloromethane). Dye adsorption breakthroughs include [Ln(L)]·Cl}n for Congo Red (2724 mg g⁻¹) and DUT-23(Cu) for Methylene Blue (814 mg g⁻¹). Zn-MOF(NH₂) shows extraordinary heavy metal capacities: 4874 mg g⁻¹ (Pb²⁺), 4624 mg g⁻¹ (Cu²⁺), 4261 mg g⁻¹ (Hg²⁺). PPCP adsorption features Ni/Co-MOF@CMC (625 mg g⁻¹ tetracycline), while MOF-525 removes 807 mg g⁻¹ tetracycline (antibiotics). ZIF-8 leads pesticide adsorption (367 mg g⁻¹ prothiofos). These high capacities, driven by acid-base, electrostatic, π-π, and H-bonding interactions, underscore MOF versatility. Future research should focus on AI design, industrial scaling, and circular economy integration to position MOFs as indispensable tools for achieving UN SDGs.