To find sustainable water solutions, the development of high capacity, scalable robust adsorbents and mechanistic insight about their performance offers the potential to effectively address the global challenges of water scarcity and water contamination. We herein rationally design Zr-cluster defective MOF-808 (MOF-808_def) with exposed carboxyl groups, a robust zirconium metal–organic framework (Zr-MOF), exhibiting high adsorption capacity (q_max ∼ 296 mg·g⁻¹) coupled with high selectivitity for tetracycline (TC) antibiotics, outperforming other water-stable MOFs, commercial and inorganic nano-adsorbents. MOF-808_def functions well across a wide range of contaminant concentrations (from trace to high-concentration) and even in harsh conditions (e.g., high acidity and salinity). Both experimental and simulation results indicate that the mechanism of adsorption involves both physisorption and chemisorption via hydrogen bonding, electrostatic interactions (EIs) and C-O-C covalent bonding via esterification. Computational studies confirm that hydrogen bonding plays a key role in strong guest–host interactions between TCs and MOF-808_def. Further, defects resulting from missing-Zr-clusters in MOF-808_def are confirmed to enhance adsorption performance. Specifically, the defect sites present exposed carboxyl groups from MOF-808_def linker ligands that selectively react with –OH groups (phenol and tertiary alcohol moieties) in TC via esterification. These defects drive highly selective adsorption even at low concentrations of TCs (e.g., 500 ppb). Aiming for more than enhanced performance, economic estimation and scalable engineered reactor tests revealed that MOF-808_def and its nano-composites are free of environmental risks and offer promise for sustainable water treatment at pilot scale. The use of defect-engineering rationales is a molecule-level design concept that could be generally useful for the development of the next generation of MOF-based nano-adsorbents for sustainable water treatment applications.

为了找到可持续的水解决方案，开发高容量、可扩展的强大吸附剂和对其性能的机械洞察力提供了有效解决全球水资源短缺和水污染挑战的潜力。我们在此合理地设计了具有暴露羧基的Zr 簇缺陷 MOF-808 (MOF-808 _{def )，这是一种坚固的锆金属-有机骨架 (Zr-MOF)，具有高吸附容量 (q max}  ∼ 296 mg·g ^-1 )再加上对四环素 (TC) 抗生素的高选择性，优于其他水稳定 MOF、商业和无机纳米吸附剂。MOF-808_分辨率在各种污染物浓度（从痕量到高浓度）甚至在恶劣条件下（例如，高酸度和盐度）都能很好地发挥作用。实验和模拟结果均表明吸附机理包括通过氢键、静电相互作用 (EI) 和通过酯化作用的 COC 共价键的物理吸附和化学吸附。计算研究证实，氢键在 TC 和 MOF-808 _def之间的强客体 - 主体相互作用中起关键作用。_{此外，证实 MOF-808 def}中缺少 Zr 簇导致的缺陷可提高吸附性能。具体来说，缺陷位点存在来自 MOF-808 的暴露羧基_{def连接配体}通过酯化选择性与 TC 中的 -OH 基团（苯酚和叔醇部分）反应。即使在低浓度的 TC（例如，500 ppb）下，这些缺陷也会驱动高度选择性吸附。旨在提高性能、经济估算和可扩展的工程反应堆测试表明，MOF-808 _def及其纳米复合材料没有环境风险，并为中试规模的可持续水处理提供了希望。缺陷工程原理的使用是一种分子级设计概念，通常可用于开发用于可持续水处理应用的下一代基于 MOF 的纳米吸附剂。