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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]

Metal–organic frameworks (MOFs) have evolved as an exciting class of materials in the domain of porous materials. The unique features of these materials arise from the combined properties of metal ions/clusters and organic struts which form the building blocks of these fascinating architectures. Among other multifarious applications, MOFs have shown tremendous applications as sensory materials for a wide variety of species. The signal transduction induced mechanism in these confined nanospaces generate optical output in response to a particular analyte which can be detected by wide variety of detection techniques. Fluorometric methods of sensing is one of widely studied method over past few decades. MOF‐based fluorometric detection is a key research theme developed over the past few years. In this review, we give a brief overview of the recent developments of MOFs as "turn‐on" sensors for a wide range of analytes (viz. cations, anions, volatile organic compounds (VOCs), etc.). [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]

Metal-organic frameworks, popularly known as MOFs, have come of age—thanks to custom-built design principles enabling them to serve a myriad of task-specific applications. In an era where >6000 new MOFs are annually published, driven by academic research, a new generation of MOFs that can find use in niche markets is on the rise. One of the foremost challenges that plague the translation of MOFs into materials suited for commercialization is their water-influenced degradation, largely accountable to hydrolytic instability and the ubiquity of water. Hydrophobic MOFs offer one of the most promising solutions which can enable these porous materials to leverage their functionalization guided properties even under extreme humid conditions, a criterion that application-ready materials should necessarily serve. In this contribution, our discussion focuses on the state-of-the-art hydrophobic MOFs and MOF-derived composites. Outlining a brief overview of the structure-property correlation aspects in each of these promising hydrophobic MOFs with little or no influence exhibited to water and/or humidity, a future outlook is put forward to enable potentially better design strategies leading to futuristic MOFs tolerant to water/moisture. Concise premise of this review allows us to limit our discussion to the design principles in action behind the most hydrophobic MOFs/derived composites reported thus far and to discuss their prime applications viz., oil/water separation inclusive of self-cleaning, hydrocarbon separation, and tackling marine oil spillage. When synergized, such improved porous material design approaches lean toward a greener environment of tomorrow. [ABSTRACT FROM AUTHOR]

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Metal–organic frameworks (MOFs) or porous coordination polymers (PCPs) are open, crystalline supramolecular coordination architectures with porous facets. These chemically tailorable framework materials are the subject of intense and expansive research, and are particularly relevant in the fields of sensory materials and device engineering. As the subfield of MOF-based sensing has developed, many diverse chemical functionalities have been carefully and rationally implanted into the coordination nanospace of MOF materials. MOFs with widely varied fluorometric sensing properties have been developed using the design principles of crystal engineering and structure–property correlations, resulting in a large and rapidly growing body of literature. This work has led to advancements in a number of crucial sensing domains, including biomolecules, environmental toxins, explosives, ionic species, and many others. Furthermore, new classes of MOF sensory materials utilizing advanced signal transduction by devices based on MOF photonic crystals and thin films have been developed. This comprehensive review summarizes the topical developments in the field of luminescent MOF and MOF-based photonic crystals/thin film sensory materials. [ABSTRACT FROM AUTHOR]

Two porous hydrogen-bonded organic frameworks (HOFs) based on arene sulfonates and guanidinium ions are reported. As a result of the presence of ionic backbones appended with protonic source, the compounds exhibit ultra-high proton conduction values ( σ) 0.75× 10−2 S cm−1 and 1.8×10−2 S cm−1 under humidified conditions. Also, they have very low activation energy values and the highest proton conductivity at ambient conditions (low humidity and at moderate temperature) among porous crystalline materials, such as metal-organic frameworks (MOFs) and covalent organic frameworks (COFs). These values are not only comparable to the conventionally used proton exchange membranes, such as Nafion used in fuel cell technologies, but is also the highest value reported in organic-based porous architectures. Notably, this report inaugurates the usage of crystalline hydrogen-bonded porous organic frameworks as solid-state proton conducting materials. [ABSTRACT FROM AUTHOR]

Prompt and selective detection of nitro explosives in the aqueous phase is in high demand to meet homeland security and environmental concerns. Herein we report the chemically stable porous metal organic framework UiO-68@NH2 with a pendant recognition site for selective detection of the nitro-aromatic explosive TNP in the aqueous phase. The pendant Lewis basic amine moieties are expected to selectively interact with TNP via electrostatic interactions and act as recognition sites for TNP. The MOF can detect the presence of TNP in water at a concentration as low as 0.4 ppm with a response time of a few seconds. In addition, both excitation and emission wavelengths of the MOF are in the visible region. The high selectivity was observed even in the presence of competing nitro analytes in the aqueous phase. The quenching constant for TNP was found to be 5.8 × 104 M−1 which is 23 times higher than that for TNT and for RDX, demonstrating superior and selective quenching ability. This unprecedented selectivity is ascribed to electron-transfer and energy-transfer mechanisms as well as electrostatic interactions between TNP and the MOF. An MOF-coated paper strip that we prepared demonstrated fast and selective response to TNP in water, which represents a first step towards a practical application. [ABSTRACT FROM AUTHOR]

The development of solid-state proton-conducting materials with high conductivity that operate under both anhydrous and humidified conditions is currently of great interest in fuel-cell technology. A 3D metal-organic framework (MOF) with acid-base pairs in its coordination space that efficiently conducts protons under both anhydrous and humid conditions has now been developed. The anhydrous proton conductivity for this MOF is among the highest values that have been reported for MOF materials, whereas its water-assisted proton conductivity is comparable to that of the organic polymer Nafion, which is currently used for practical applications. Unlike other MOFs, which conduct protons either under anhydrous or humid conditions, this compound should represent a considerable advance in the development of efficient solid-state proton-conducting materials that work under both anhydrous and humid conditions. [ABSTRACT FROM AUTHOR]

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]

Keywords: Luminescence; Metal-organic frameworks; Porous coordination polymers; Sensing; Turn-on sensors The practical usability in terms of stability and performance make MOFs a stand-out class of materials for turn-on fluorescent sensing. Luminescence, Metal-organic frameworks, Porous coordination polymers, Sensing, Turn-on sensors. [Extracted from the article]

Front Cover: Stabilizing Metal-Organic Polyhedra (MOP): Issues and Strategies (Chem. B Cage compounds b : Metal-organic polyhedra (MOPs) are discrete, metal-organic molecular entities composed of edge-sharing molecular polygons or connected molecular vertices that offer much promise as porous materials owing to their well-defined structures and solution processability. Cage compounds, hydrolytic stability, hydrophobicity, metal-organic polyhedra, self-assembly. [Extracted from the article]

In recent years, environmental pollution and its effects have demanded attention from all over the world. In this context, water pollution has been regarded as one of the biggest threats to all living forms among all types of pollution in recent years, and things are forecasted to get worse if remediating steps are not adopted soon. Water recycling has gained importance in the twenty-first century as more areas of the world experience a water crisis. Given this, ground-water pollution by heavy metal-based toxic oxo-pollutants such as CrO 4 2−, Cr 2 O 7 2−, AsO 4 3−, SeO 3 2−, SeO 4 2−, TcO 4 −, ReO 4 − etc. have been becoming rapidly growing global concerns and pose a major risk to both human health and the environment. These hazardous and persistent chemicals have been designated as priority pollutants by the US Environmental Protection Agency (EPA) due to their extreme toxicity following bioaccumulation. Therefore, it is crucial to get rid of them from contaminated water in an efficient manner. In this regard, now a days, Advanced Functional Porous Materials (AFPMs) such as metal-organic frameworks (MOFs), porous organic polymers (POPs), covalent organic frameworks (COFs), and porous hybrid composite have drawn significant attention from researchers looking into wastewater treatment owing to their advantages of tunable porosity, high surface area, and an abundance of functional groups over traditional adsorbents. This review provides an overview of the latest advancements in Advanced Functional Porous Materials, including MOFs and related porous materials, used as effective adsorbents to remove harmful oxoanions derived from heavy metals from contaminated water. Additionally, the review suggests practical solutions for ensuring the safety and cleanliness of drinking water. Furthermore, their adsorption mechanisms are discussed which may enable better designing of new MOFs/AFPMs-based adsorbents with superior performance for future study as well as for understanding the adsorption process between MOFs/AFPMs and heavy metal oxoanions contaminants. Lastly, in order to fully comprehend the developing prospects for the future, the potential and challenges of MOFs/AFPMs were thoroughly discussed. [Display omitted] • Heavy metal based toxic oxo-pollutants and Advanced Functional Porous Materials (MOFs, POPs, COFs, hybrid composites). • Recent survey of sequestration of heavy metal based toxic oxo-pollutants by different porous materials. • The interaction mechanism of different toxic oxo-pollutants with MOFs, POPs, COFs and hybrid composites are discussed. • The challenges and perspective of MOFs, and other porous materials in metal oxo-pollutants sequestration are described. [ABSTRACT FROM AUTHOR]

A homochiral luminescent porous coordination polymer, [Cd(L)(H2O)]·3H2O, with interconnected collagen like triple-helical chains has been synthesized solvothermally by using cadmium(II) salt and a newly designed d-isosorbide-based, enantiomerically pure chiral ligand. The framework is a 2D porous material and forms a 1D channel along the a axis, with the channel dimensions ∼6.2 x 4.4 Å2. The compound has high selectivity in the uptake of water and methanol over other solvents (e.g., tetrahydrofuran, ethanol, benzene, and cyclohexane) inside the channels. [ABSTRACT FROM AUTHOR]

A robust and water-stable porous coordination polymer [Cd(NDC)0.5(PCA)]•Gx (1) (H2NDC = 2,6-napthalenedicarboxylic acid, HPCA = 4-pyridinecarboxylic acid, G = guest molecules) with new network topology has been synthesized solvothermally. The framework is 3D porous material and forms a 1D channel along the c-axis, with the channel dimensions ~9.48 × 7.83 Å2. The compound has high selectivity in uptake of CO2 over other gases (H2, O2, Ar, N2, and CH4). The framework is highly stable in presence of water vapor even at 60 °C. The high CO2 selectivity over other gases and water stability makes the compound promising candidate for industrial postcombustion gas separation application. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Two isostructural coordination polymers were synthesized with cationic framework. • The pore surfaces of the frameworks are decorated with several polar groups. • Selective uptake of CO 2 over N 2 was observed for both iMOFs. Abstract Two novel two-dimensional cationic metal-organic frameworks, namely iMOF-27-Co and iMOF-27-Ni, have been synthesized at room temperature by using a prefunctionalized anhydride core based neutral N-donor ligand. Single crystal X-ray diffraction (SC-XRD) study revealed that both compounds crystallizes in the orthorhombic space group Cmcm with molecular formula {[Co 1 (L) 2 (DMF) 2 ](ClO 4) 2.x·(G)} n , {[Ni 1 (L) 2 (DMF) 2 ](ClO 4) 2.x·(G)} n (L = ligand, x·G = disordered guest molecules) respectively. Powder X-ray diffraction (PXRD) patterns reveals that all the aforementioned MOFs are isostructural in nature. Further, both the MOFs exhibited an efficient carbon dioxide (CO 2) uptake over N 2 at both low and room temperature. High isosteric heat of adsorption (Q st) has been obtained for both compounds because of strong interactions between the polar groups of the framework and CO 2 molecules. [ABSTRACT FROM AUTHOR]

A three-dimensional biporous soft porous coordination polymer containing active coordination space, made of cadmium(II) and a tripodal carboxylate ligand bearing ether linkages, was synthesized and characterized. Guest-dependent dynamic activities in the active coordination space of the soft porous crystal have been explored. We have demonstrated controlled chemical blocking and unblocking of active pores of the dynamic framework along with guest-dependent contraction and expansion of the channels by single-crystal-to-single-crystal structural transformation studies. Detailed studies revealed up to 70% contraction of the void volume and almost a 100 times increase in gas sorption by controlled phases obtained by guest switching. These types of soft materials with porous scaffolds, also known as soft porous crystals, may have general implications in the preparation of intelligent host materials with zeolitic properties and enzyme-like specificity. [ABSTRACT FROM AUTHOR]