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Water pollution is a growing threat to humanity due to the pervasiveness of contaminants in water bodies. Significant efforts have been made to separate these hazardous components to purify polluted water through various methods. However, conventional remediation methods suffer from limitations such as low uptake capacity or selectivity, and current water quality standards cannot be met. Recently, advanced porous materials (APMs) have shown promise in improved segregation of contaminants compared to traditional porous materials in uptake capacity and selectivity. These materials feature merits of high surface area and versatile functionality, rendering them ideal platforms for the design of novel adsorbents. This Review summarizes the development and employment of APMs in a variety of water treatments accompanied by assessments of task‐specific adsorption performance. Finally, we discuss our perspectives on future opportunities for APMs in water purification. [ABSTRACT FROM AUTHOR]

Water pollution is a growing threat to humanity due to the pervasiveness of contaminants in water bodies. Significant efforts have been made to separate these hazardous components to purify polluted water through various methods. However, conventional remediation methods suffer from limitations such as low uptake capacity or selectivity, and current water quality standards cannot be met. Recently, advanced porous materials (APMs) have shown promise in improved segregation of contaminants compared to traditional porous materials in uptake capacity and selectivity. These materials feature merits of high surface area and versatile functionality, rendering them ideal platforms for the design of novel adsorbents. This Review summarizes the development and employment of APMs in a variety of water treatments accompanied by assessments of task‐specific adsorption performance. Finally, we discuss our perspectives on future opportunities for APMs in water purification. [ABSTRACT FROM AUTHOR]

Uranium extraction from seawater (UES), a potential approach to securing the long-term uranium supply and sustainability of nuclear energy, has experienced significant progress in the past decade. Promising adsorbents with record-high capacities have been developed by diverse innovative synthetic strategies, and scale-up marine field tests have been put forward by several countries. However, significant challenges remain in terms of the adsorbents' properties in complex marine environments, deployment methods, and the economic viability of current UES systems. This review presents an up-to-date overview of the latest advancements in the UES field, highlighting new insights into the mechanistic basis of UES and the methodologies towards the function-oriented development of uranium adsorbents with high adsorption capacity, selectivity, biofouling resistance, and durability. A distinctive emphasis is placed on emerging electrochemical and photochemical strategies that have been employed to develop efficient UES systems. The most recent achievements in marine tests by the major countries are summarized. Challenges and perspectives related to the fundamental, technical, and engineering aspects of UES are discussed. This review is envisaged to inspire innovative ideas and bring technical solutions towards the development of technically and economically viable UES systems. [ABSTRACT FROM AUTHOR]

Uncontrolled mixing remains the primary hurdle impeding the practical application of reverse electrodialysis (RED) to harvest Gibbs free energy in the form of salinity gradients. Improving the permselectivity of membranes is therefore essential, with ionic density being one of the most critical factors. Herein, it is systematically investigated how the charge population in nanofluidic membranes affects the ionic charge separation and consequently the accompanying power density. To establish this relationship, the effect of the ionic density is decoupled from the impact of pore structure using a multivariate strategy to construct covalent‐organic‐framework‐based membranes, in which the content of ionic sites can be precisely manipulated from 0 to 0.18 C m−2, a range that has rarely been experimentally explored. Beyond the region reported (0.002–0.06 C m−2), wherein increasing pore surface charge density of the membrane enhances permselectivity and leads to a greater osmotic voltage, a sharp volcano‐like curve is observed. The optimal membrane affords record‐high power outputs among membrane systems, one order of magnitude higher than the value set for commercialization. The study provides insights into the impact of ionic density of the membrane on osmotic energy harvesting that can guide RED stack design to advance sustainable energy generation from natural salinity gradients. [ABSTRACT FROM AUTHOR]

Nitrogen‐containing compounds, as an important class of chemicals, have been used widely in pharmaceuticals, materials synthesis. Transition metal‐catalyzed reductive amination of an aldehyde or a ketone with ammonia or an amine has been proved to be an efficient and practical method for the preparation of nitrogen‐containing compounds in academia and industry for a century. Given the above, several effective methods using transition metals have been developed in recent years. Noble transition metals like Pd, Pt, and Au‐based catalysts have been predominately used in reductive amination. Because of their high prices, strict official regulations of residues in pharmaceuticals, and deleterious effects on the biological system, their industrial applications are severely hampered. With the increasing sustainable and environmental problems, the Earth‐abundant transition metals including Ti, Fe, Co, Ni, and Zr have also been investigated for the reductive amination reaction and showed great potential to the advancement of sustainable and cost‐effective reductive amination processes. This critical review will mainly summarize the work using Earth‐abundant metals. The effects of different transition metals used in catalytic reduction amination were discussed and compared, and some suggestions were given. The last section highlights the catalytic activities of bi‐ and tri‐metallic catalysts. Indeed, this latter family is very promising and simultaneously benefits from increased stability, and selectivity, compared to monometallic NPs, due to synergistic substrate activation. Few comprehensive reviews focusing on Earth‐abundant transition metals catalyst has been published since 1948, although several authors reported some summaries dealing with one or the other part of this aspect. It is hoped that this critical review will inspire researchers to develop new efficient and selective earth‐abundant metal catalysts for highly, environmentally sustainable reductive amination methods, as well as improve the pharmaceutical industry and related chemical synthesis company traditional method with the utilization of the green method widely. [ABSTRACT FROM AUTHOR]

The development of Earth-abundant, reusable and non-toxic heterogeneous catalysts to be applied in the pharmaceutical industry for bio-active relevant compound synthesis remains an important goal of general chemical research. N-methylated compounds, as one of the most essential bioactive compounds, have been widely used in the fine and bulk chemical industries for the production of high-value chemicals. Herein, an environmentally friendly and simplified method for the preparation of graphene encapsulated Ni/NiO nanoalloy catalysts (Ni/NiO@C) was developed for the first time, for the highly selective synthesis of N-methylated compounds using various functional amines and aldehydes under easy to handle, and industrially applicable conditions. A large number of primary and secondary amines (more than 70 examples) could be converted to the corresponding N,N-dimethylamines with the participation of different functional aldehydes, with an average yield of over 95%. A gram-scale synthesis also demonstrated a similar yield when compared with the benchmark test. In addition, it was further proved that the catalyst could easily be recycled because of its intrinsic magnetism and reused up to 10 times without losing its activity and selectivity. Also, for the first time, the tandem synthesis of N,N-dimethylamine products in a one-pot process, using only a single earth-abundant metal catalyst, whose activity and selectivity were more than 99% and 94%, respectively, for all tested substrates, was developed. Overall, the advantages of this newly developed method include operational simplicity, high stability, easy recyclability, cost-effectiveness of the catalyst, and good functional group compatibility for the synthesis of N-methylation products as well as the industrially applicable tandem synthesis process. [ABSTRACT FROM AUTHOR]

Various robust, crystalline, and porous organic frameworks based on in situ‐formed imine‐linked oligomers were investigated. These oligomers self‐assembled through collaborative intermolecular hydrogen bonding interactions via liquid–liquid interfacial reactions. The soluble oligomers were kinetic products with multiple unreacted aldehyde groups that acted as hydrogen bond donors and acceptors and directed the assembly of the resulting oligomers into 3D frameworks. The sequential formation of robust covalent linkages and highly reversible hydrogen bonds enforced long‐range symmetry and facilitated the production of large single crystals, with structures that were unambiguously determined by single‐crystal X‐ray diffraction. The unique hierarchical arrangements increased the steric hindrance of the imine bond, which prevented attacks from water molecules, greatly improving the stability. The multiple binding sites in the frameworks enabled rapid sequestration of micropollutant in water. [ABSTRACT FROM AUTHOR]

Various robust, crystalline, and porous organic frameworks based on in situ‐formed imine‐linked oligomers were investigated. These oligomers self‐assembled through collaborative intermolecular hydrogen bonding interactions via liquid–liquid interfacial reactions. The soluble oligomers were kinetic products with multiple unreacted aldehyde groups that acted as hydrogen bond donors and acceptors and directed the assembly of the resulting oligomers into 3D frameworks. The sequential formation of robust covalent linkages and highly reversible hydrogen bonds enforced long‐range symmetry and facilitated the production of large single crystals, with structures that were unambiguously determined by single‐crystal X‐ray diffraction. The unique hierarchical arrangements increased the steric hindrance of the imine bond, which prevented attacks from water molecules, greatly improving the stability. The multiple binding sites in the frameworks enabled rapid sequestration of micropollutant in water. [ABSTRACT FROM AUTHOR]

Biological pores regulate the cellular traffic of a diverse collection of molecules, often with extremely high selectivity. Given the ubiquity of charge‐based separation in nature, understanding the link between the charged functionalities and the ion transport activities is essential for designing delicate separations, with the correlation being comparatively underdeveloped. Herein, the effect of charge density from the impact of pore structure is decoupled using a multivariate strategy for the construction of covalent organic framework‐based membranes. How the density of charged sites in the nanofluidic membranes affect the ion transport activity with particular emphasis on Li+ and Mg2+ ions, relevant to the challenge of salt‐lake lithium mining is systematically investigated. Systematic control of the charge distribution produces membranes with numerous advantages, overcoming the long‐term challenge of Li+/Mg2+ separation. The top membrane exhibits an outstanding equilibrium selectivity for Li+ over Mg2+ and operational stability under diffusion dialysis and electrodialysis conditions (Li+/Mg2+ up to 500), qualifying it as a potential candidate for lithium extraction. It is anticipated that the developed nanofluidic membrane platform can be further leveraged to tackle other challenges in controlled separation processes. [ABSTRACT FROM AUTHOR]

Preorganization is a basic design principle used by nature that allows for synergistic pathways to be expressed. Herein, a full account of the conceptual and experimental development from randomly distributed functionalities to a convergent arrangement that facilitates cooperative binding is given, thus conferring exceptional affinity toward the analyte of interest. The resulting material with chelating groups populated adjacently in a spatially locked manner displays up to two orders of magnitude improvement compared to a random and isolated manner using uranium sequestration as a model application. This adsorbent shows exceptional extraction efficiencies, capable of reducing the uranium concentration from 5 ppm to less than 1 ppb within 10 min, even though the system is permeated with high concentrations of competing ions. The efficiency is further supported by its ability to extract uranium from seawater with an uptake capability of 5.01 mg g−1, placing it among the highest‐capacity seawater uranium extraction materials described to date. The concept presented here uncovers a new paradigm in the design of efficient sorbent materials by manipulating the spatial distribution to amplify the cooperation of functions. [ABSTRACT FROM AUTHOR]

Hydrothermal liquefaction (HTL) technology was employed to investigate the feasibility of recovering energy from penicillin mycelial waste (PMW) with the help of TG, Py-GC/MS and GC-MS techniques; meanwhile, the nutrients in aqueous phase were also analyzed by spectrophotometry methods. The effects of operating conditions, including hydrothermal temperature (240–300 °C), duration time (20–60 min), total solid ratio (5–15%) and their interactive reactions were concurrently evaluated via response surface methodology. Results demonstrated that operating temperature was found to be the dominant variable affecting the HTL of PMW. Based on the optimal conditions of 298 °C, 60 min and 14.85%, heavy oil derived from PMW was comparable with algal-derived bio-oil as it possessed the highest energy recovery efficiency (42.95%) with a calorie value of 32.84 MJ/kg and a yield of 24.93%. GC/MS results indicated that heavy oil mainly consisted of N-containing compounds (36.73%) and aromatic compounds (31.07%), which might be contributed to the hydrolysis of protein and the aromatization of intermediates, respectively. Besides, more than 65% of nitrogen and 40% of carbon were enriched in aqueous phase, suggesting the possibility of further recycling for algae cultivation, fermentation and anaerobic digestion. Image 1 • The potential usage of antibiotic wastes as biofuel via hydrothermal liquefaction. • Optimizing the process of hydrothermal liquefaction via response surface methods. • Individual and interactive effects of operation conditions on bio-oil properties. • The feasible of recovering nutrients from aqueous phase. [ABSTRACT FROM AUTHOR]

Four new metal–organic complexes of the formula [CrL′Cl2] (1), [CuL′Cl2] (2), [MnL′′Cl2·H2O] (3), and [NiL′′(OH)2·2NO3] (4) [L′=N-(1-Pyrazin-2-yl-ethylidene)-ethane-1,2-diamine, L′′2=N,N′-Bis-(1-pyrazin-2-yl-ethylidene)-ethane-1,2-diamine] have been synthesized and characterized by infrared method, elemental analysis, X-ray powder diffraction analysis, and single-crystal X-ray diffraction techniques. Their heat stability was tested by thermo gravimetric analyzer. X-ray structure analysis reveals that complexes 1–4 are all 0 D structure. The L ligand have many types of coordination modes that make these complexes as having different configuration π–π stackings and/or hydrogen bonding interactions, which seem to be effective in stabilizing these crystal structures. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are an emerging class of functional nanostructures with intriguing properties, due to their unprecedented combination of high crystallinity, tunable pore size, large surface area, and unique molecular architecture. The range of properties characterized in COFs has rapidly expanded to include those of interest for numerous applications ranging from energy to environment. Here, a background overview is provided, consisting of a brief introduction of porous materials and the design feature of COFs. Then, recent advancements of COFs as a designer platform for a plethora of applications are emphasized together with discussions about the strategies and principles involved. Finally, challenges remaining for this type material for real applications are outlined. Covalent organic frameworks (COFs) are porous crystalline polymers with tunable composition and structural architecture, enabling precise control over functionality, density, and spatial arrangement. This universal control makes them a particularly promising platform for task‐led design. Recent advancements of COFs for numerous applications are reviewed and the challenges and opportunities associated with processing and large‐scale synthesis are discussed. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are an emerging class of functional nanostructures with intriguing properties, due to their unprecedented combination of high crystallinity, tunable pore size, large surface area, and unique molecular architecture. The enormous possible design space available within COFs provides virtually unlimited room for imagination, allowing designed incorporation of different functionalities. In article number 1801410, Qi Sun, Shengqian Ma, and co‐workers review the recent advancements of COFs for numerous applications. [ABSTRACT FROM AUTHOR]