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Extraction of gold from secondary resources such as electronic waste (e‐waste) has become crucial in recent times to compensate for the gradual scarcity of the noble metal in natural mines. However, designing and synthesizing a suitable material for highly efficient gold recovery is still a great challenge. Herein, we have strategically designed rapid fabrication of an ionic crystalline hybrid aerogel by covalent threading of an amino‐functionalized metal‐organic polyhedra with an imine‐linked chemically stable covalent organic framework at ambient condition. The hierarchically porous ultra‐light aerogel featuring imine‐rich backbone, high surface area, and cationic sites have shown fast removal, high uptake capacity (2349 mg/g), and excellent selectivity towards gold sequestration. Besides, the aerogel can extract ultra‐trace gold‐ions from different terrestrial water bodies, aiming towards safe drinking water. This study demonstrates the great potential of the composite materials based on a novel approach to designing a hybrid porous material for efficient gold recovery from complex water matrices. [ABSTRACT FROM AUTHOR]

Preferential trapping of a selected metal-oxoanion from a mixture of other metal-oxoanionic toxic pollutants in water has been demonstrated by implementing energy-efficient adsorption followed by the ion-exchange method, utilizing a hydrolytically stable cationic metal–organic framework (MOF). The cationic MOF exhibits ultrafast and selective extraction efficiency towards ReO4− (a surrogate anion of radioactive TcO4−) over other metal-oxoanions in contaminated water systems. [ABSTRACT FROM AUTHOR]

Over the last few decades, given the impending global energy and environmental crises, paramount development in nuclear energy as an alternative high power density and low-carbon energy source has been widely observed. However, this development is hindered due to certain problems associated with nuclear reactors, including the emission of volatile radioactive substances, like organic iodides and iodine, which must be eliminated before releasing the off-gas. These substances include methyl iodide (CH3I), ethyl iodide (CH3CH2I), and iodine, which are exceedingly harmful to both the environment and human health. Although several porous solid adsorbents have been successfully employed to sequester organic iodides (generally CH3I) from the vapor phase, the majority of the earlier investigations have largely focused on the saturation capacity and kinetic study of CH3I capture. However, the importance of the porous adsorbents' strategic functions in the unique binding interaction with organic iodides has been grossly underappreciated and poorly understood. Also, certain crucial difficulties pertaining to the practical capturing of radioactive organic iodides from nuclear waste were thwarted in the endeavors to construct innovative adsorbents. Herein, we have demonstrated a systematic strategy-driven study to understand the roles of framework-integrated functionalities towards organic iodide sequestration by varying the number of N-heteroatomic sites in a series of chemically stable porous covalent organic frameworks (COFs). The CH3I adsorption capacity was found to be positively correlated with the porosity or surface area as well as with the N-heteroatomic or heterocyclic functionalities, such as the imine, pyridine, and triazine sites of these COFs. Under both static and dynamic conditions, all the COFs exhibited high CH3I sorption capacities through the N-methylation reaction mechanism. This work is of fundamental importance to understanding the CH3I adsorption mechanisms and also offers direction for the design and development of novel adsorbents for relevant applications. [ABSTRACT FROM AUTHOR]

In case of pollutant segregation, fast mass diffusion is a fundamental criterion in order to achieve improved performance. The rapid mass transport through porous materials can be achieved by availing large open pores followed by easy and complete accessibility of functional sites. Inducing macroporosity into such materials could serve as ideal solution providing access to large macropores that offer unhindered transport of analyte and full exposure to interactive sites. Moreover, the challenge to configure the ionic‐functionality with macroporosity could emerge as an unparalleled avenue toward pollutants separation. Herein, we strategized a synthetic protocol for construction of a positively charged hierarchically‐porous ordered interconnected macro‐structure of organic framework where the size and number of macropores can easily be tuned. The ordered macropores with strong electrostatic interaction synergistically exhibited ultrafast removal efficiency towards various toxic pollutants. [ABSTRACT FROM AUTHOR]

Owing to detrimental impact of cyanide ion (CN−) towards the entire living system as well as its availability in drinking water, it has become very important developing potential sensory materials for the selective and sensitive recognition of CN− ions in water. In the domain of sensory materials, luminescent metal‐organic frameworks (LMOFs) have been considered as a promising candidate owing to their unique host‐guest interaction, where MOFs can serve as an ideal scaffold for encapsulating relevant guest molecules rendering specific functionality. In this study, a post‐synthetically modified MOF (viz. CuCl2@MOF‐867) was applied to recognize cyanide (CN−) ions in water via "turn‐on" response. The bipyridyl functionalities in MOF‐867 were used to perform post‐synthetic metalation to infiltrate CuCl2 inside porous architecture of the MOF. Moreover, a CuCl2@MOF‐867 based probe demonstrated highly selective and sensitive aqueous phase recognition of CN− ions even in the presence of other interfering anions such as Br−, NO3−, I−, SO42−, OAc−, SCN−, NO2−, etc. The selective binding of CN− ions to the copper‐metal center has led to the generation of stable Cu(CN)2 species. This phenomenon has further resulted in a fluorescence turn‐on response. The aqueous phase cyanide detection by the rationally modified MOF system exhibited very low limit of detection (0.19 μM), which meets the standardized limit stated by World Health Organization (WHO) that is 1.9 μM. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Environmental Remediation, Ionic-Functionality, Macro-Structure, Organic-Framework, Pollutants Removal Keywords: Environmental Remediation; Ionic-Functionality; Macro-Structure; Organic-Framework; Pollutants Removal EN Environmental Remediation Ionic-Functionality Macro-Structure Organic-Framework Pollutants Removal 1 1 1 01/02/23 20230102 NES 230102 B Energy-economic separation b of a wide array of toxic pollutants from water using macro-micro hierarchical pores crafted in an ionic organic framework is reported by Sujit K. Ghosh et al. in their Research Article (e202214095). Inside Cover: Ordered Macro/Microporous Ionic Organic Framework for Efficient Separation of Toxic Pollutants from Water (Angew. [Extracted from the article]

Environmental Remediation, Ionic-Functionality, Macro-Structure, Organic-Framework, Pollutants Removal The uniformly distributed ordered interconnected macropores in synergy with charged viologen units demonstrated swift diffusion of analytes, thus achieving ultrafast adsorption potency toward various organic-inorganic toxic contaminants from water. Keywords: Environmental Remediation; Ionic-Functionality; Macro-Structure; Organic-Framework; Pollutants Removal EN Environmental Remediation Ionic-Functionality Macro-Structure Organic-Framework Pollutants Removal 1 1 1 01/02/23 20230102 NES 230102 B Energy-economic separation b of a wide array of toxic pollutants from water using macro-micro hierarchical pores crafted in an ionic organic framework is reported by Sujit K. Ghosh et al. in their Research Article (e202214095). [Extracted from the article]

Keywords: iron metal ions; metal-organic frameworks; metal ions; sensing; selective detection EN iron metal ions metal-organic frameworks metal ions sensing selective detection 1 1 1 04/14/22 20220412 NES 220412 B The role of the organic building units b of MOFs towards selective detection of a targeted metal cation (Fe SP 3+ sp ) has been demonstrated by systematic screening by varying the number of Lewis basic (pyridyl-N atoms) sites in a series of isostructural metal-organic frameworks (MOFs). Iron metal ions, metal-organic frameworks, metal ions, sensing, selective detection. [Extracted from the article]

Cover Feature: Selective and Sensitive Fluorescence Turn-On Detection of Cyanide Ions in Water by Post Metallization of a MOF (ChemPlusChem 1/2022) Cyanide ion, fluorescence, metal-organic framework, selective recognition, sensing Keywords: cyanide ion; fluorescence; metal-organic framework; selective recognition; sensing EN cyanide ion fluorescence metal-organic framework selective recognition sensing 1 1 1 02/01/22 20220101 NES 220101 B The Cover Feature shows b a potential sensory material (CuCl SB 2 sb @MOF-867), which has been developed by post metallization (CuCl SB 2 sb ) of a water stable luminescent metal-organic framework, namely MOF-867, constructed with bipyridyl functionality as organic linker. [Extracted from the article]