Sahel Fajal

, are destroying the ecological balance of the environment. Therefore, systematic monitoring and effective remediation of these toxic pollutants either by adsorptive removal or by catalytic degradation are of great significance. From this viewpoint, porous organic polymers (POPs), being two- or three-dimensional polymeric materials, constructed from small organic molecules connected with rigid covalent bonds have come forth as a promising platform toward various leading applications, especially for efficient environmental remediation. Their unique chemical and structural features including high stability, tunable pore functionalization, and large surface area have boosted the transformation of POPs into various macro-physical forms such as thick and thin-film membranes, which led to a new direction in advanced level pollutant removal, separation and catalytic degradation. In this review, our focus is to highlight the recent progress and achievements in the strategic design, synthesis, architectural-engineering and applications of POPs and their composite materials toward environmental remediation. Several strategies to improve the adsorption efficiency and catalytic degradation performance along with the in-depth interaction mechanism of POP-based materials have been systematically summarized. In addition, evolution of POPs from regular powder form application to rapid and more efficient size and chemo-selective, "real-time" applicable membrane-based application has been further highlighted. Finally, we put forward our perspective on the challenges and opportunities of these materials toward real-world implementation and future prospects in next generation remediation technology.

Multiple functional groups decorated ionic macroporous metal–organic framework (MOF) for large-scale, selective uranium recovery from unspiked natural seawater.

Hybrid bromide perovskites (HBPs) have emerged as a promising candidate in optoelectronic applications, although instability of the materials under working conditions has retarded the progress toward commercialization. As a rational approach to address this core issue, we herein report the synthesis of a series of ultrastable composite materials, wherein HBP nanocrystals (NCs) have been stabilized within a well-known chemically stable metal–organic framework (MOF) viz. zeolitic imidazolate framework (ZIF-8) via a pore-encapsulated solvent-directed (PSD) approach. The composites maintain their structural integrity as well as photoluminescence (PL) properties upon dipping into a wide range of polar solvents including water (even in boiling conditions), prolonged exposure to UV irradiation, and elevated temperature for longer periods of time. Further, on the basis of high stability, HBP@MOF composites have been demonstrated as heterogeneous photocatalysts to degrade toxic organic pollutants directly in water.

Abstract Considering the importance of sustainable nuclear energy, effective management of radioactive nuclear waste, such as sequestration of radioiodine has inflicted a significant research attention in recent years. Despite the fact that materials have been reported for the adsorption of iodine, development of effective adsorbent with significantly improved segregation properties for widespread practical applications still remain exceedingly difficult due to lack of proper design strategies. Herein, utilizing unique hybridization synthetic strategy, a composite crystalline aerogel material has been fabricated by covalent stepping of an amino-functionalized stable cationic discrete metal-organic polyhedra with dual-pore containing imine-functionalized covalent organic framework. The ultralight hybrid composite exhibits large surface area with hierarchical macro-micro porosity and multifunctional binding sites, which collectively interact with iodine. The developed nano-adsorbent demonstrate ultrahigh vapor and aqueous-phase iodine adsorption capacities of 9.98 g.g −1 and 4.74 g.g −1 , respectively, in static conditions with fast adsorption kinetics, high retention efficiency, reusability and recovery.

Metal-organic polyhedra (MOPs) are discrete, metal-organic molecular entities composed of edge-sharing molecular polygons or connected molecular vertices. Unlike the infinite metal-organic coordination networks popularized by metal-organic frameworks (MOFs), spherical MOPs, also known as nanocages, nanospheres, nanocapsules, or nanoballs, are obtained through the self-organization of metal-carboxylate or metal-pyridine/pyrimidine links to afford cage-like nanoarchitectures. MOPs offer much promise as porous materials owing to their well-defined structures and solution processability. However, these advantages become moot if their poor aqueous stability and/or guest-removal-induced aggregation handicaps remain unaddressed. The concise premise of this contribution limits our discussion to the design principles in action behind recent developments in stable carboxylate MOPs. To highlight the structure-property relationships between the structural and compositional features of these metal carboxylate polyhedra, related scientific challenges and state-of-the-art research directions for further exploration are presented in brief.