Environmental pollution and its after-effects have become global concerns in recent years. Among all types of pollution, water pollution has been considered as a major threat in recent years; this problem will be even worse in the near future. In the 21st century, water recycling has become a crucial issue as more regions across the globe are witnessing a water crisis. Detoxification of wastewater via adsorptive removal or photocatalytic degradation for achieving purified and drinkable water has been determined as environmentally benign, energy economic and cost-effective. In this context, porous materials have gained enormous research consideration for detection of contaminants in effluents and for treatment of wastewater. A combination of high porosity, robustness and structural tunibility makes these nanosorbents stand out as materials in environmental remediation. Metal–organic frameworks, covalent organic frameworks and porous organic solids are among the versatile porous materials extensively investigated toward clean environment application. This review intends to provide a summarized compilation of recent research progress in sensing and sequestration of organic pollutants in advanced porous materials.

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This review aims to provide an overview regarding the development of luminescent metal–organic frameworks (LMOFs) based sensory materials for the detection of cationic inorganic and organic water pollutants.

Water contamination due to heavy metal-based toxic oxo-anions (such as CrO4 2– and TcO4 –) is a critical environmental concern that demands immediate mitigation. Herein, we present an effort to counter this issue by a novel chemically stable cationic metal–organic framework (iMOF-2C) with strategic utilization of a ligand with hydrophobic core, known to facilitate such oxo-anion capture process. Moreover, the compound exhibited very fast sieving kinetics for such oxo-anions and a very high uptake capacity for CrO4 2– (476.3 mg g–1) and ReO4 – (691 mg g–1), while the latter being employed as a surrogate analogue for radioactive TcO4 – anions. Notably, the compound showed excellent selectivity even in the presence of other competing anions such as NO3 –, Cl–, SO4 2–, ClO4 –. etc.. Furthermore, the compound possesses excellent reusability (up to 10 cycles) and is also employed to a stationary phase ion column to decontaminate the aforementioned oxo-anions from water.

Large-scale generation of radioactive iodine (129I, 131I) in nuclear power plants pose a critical threat in the event of fallout, thus rendering the development of iodine sequestering materials (from both the vapor and aqueous medium) highly pivotal. Herein, we report two chemically stable ionic polymers containing multiple binding sites, including phenyl rings, imidazolium cations, and bromide anions, which in synergy promote adsorption of iodine/triiodide anions. In brief, exceptional iodine uptake (from the vapor phase) was observed at nuclear fuel reprocessing conditions. Furthermore, the ionic nature propelled removal of >99% of I3 – from water within 30 min. Additionally, benchmark uptake capacities, as well as unprecedented selectivity, were observed for I3 –anions. The excellent affinity (distribution coefficient, ∼105 mL/g) enabled iodine capture from seawater-spiked samples. Moreover, iodine-loaded compounds showed conductivity (10–4 S/cm, 10–6 S/cm), placing them among the best known conducting porous organic polymers. Lastly, DFT studies unveiled key insights in coherence with the experimental findings.