Ultrahigh Single Au Atoms Loaded Porous Aromatic Frameworks for Enhanced Photocatalytic Hydrogen Evolution.

Supported single-atom catalysts (SACs) are promising in heterogeneous catalysis because of their atom economy, unusual transformations, and mechanistic clarity. The metal SAs loading, however, limits the catalytic efficiency. Herein, an in situ pre-metallated monomer-based preparation strategy is shown to achieve ultrahigh Au SAs loading in catalyst formations.

Calix[4]arene-Derived 2D Covalent Organic Framework with an Electron Donor-Acceptor Structure: A Visible-Light-Driven Photocatalyst.

The calixarenes are ideal building blocks for constructing photocatalytic covalent organic frameworks (COFs), owing to their electron-rich and bowl-shaped π cavities that endow them with electron-donating and adsorption properties. However, the synthesis and structural confirmation of COFs based on calixarenes are still challenging due to their structural flexibility and conformational diversity. In this study, a calix[4]arene-derived 2D COF is synthesized using 5,11,17,23-tetrakis(p-formyl)-25,26,27,28-tetrahydroxycalix[4]arene (CHO-C4A) as the electron donor and 4,7-bis(4-aminophenyl)-2,1,3-benzothiadiazole (BTD) as the acceptor.

Ultrafine platinum nanoparticles anchored in porous aromatic frameworks for efficient hydrogen evolution reaction.

Platinum is recognized as an effective electrochemical catalyst for hydrogen generation. Herein, a novel porous aromatic framework (PAF-99) is synthesized and two strategies including preparation and post-synthesis are applied to introduce uniform platinum nanoparticles into PAF-99. The obtained platinum electrocatalysts (Pt-PAF-99 and Pt@PAF-99) exhibit great and distinct performances towards the hydrogen evolution reaction.

Gold Nanoparticles Immobilized in Porous Aromatic Frameworks with Abundant Metal Anchoring Sites as Heterogeneous Nanocatalysts.

Porous aromatic frameworks (PAFs) with rich metal coordination sites are highly effective support materials for gold nanoparticles (AuNPs), which would not only prevent AuNPs agglomeration but also facilitate mass transfer during the catalytic process. In this work, PAF-160, -161, and -162 bearing diphosphine units are synthesized via the Friedel-Crafts alkylation reaction to act as efficient platforms for AuNPs immobilization. These PAFs possess high surface areas (up to 655 m g) together with excellent stabilities, and the different linkage lengths between P centers allow more scattered and accessible sites for gold coordination.

Multi-Functionalization Integration into the Electrospun Nanofibers Exhibiting Effective Iodine Capture from Water.

Efficient capture of radioiodine from aqueous solutions is of importance for sustainable development of nuclear energy and protection of the environment. However, current adsorbents under exploration suffer from limited adsorption capacity and powder form that are unfavorable for practical applications. Herein, we applied a "multi-functionalization integration" idea to construct novel electrospun fiber adsorbents (N-MOF-PAN fibers) containing cationic quaternary ammonium groups, uncharged amine groups, and porous MOF material (UiO-66-NH), which in synergy adsorb iodine effectively from both saturated I aqueous solution and I aqueous solution.

Metal-Organic Framework Integrating Ionic Framework and Bimetallic Coupling Effect for Highly Efficient Oxygen Evolution Reaction.

Metal-organic frameworks (MOFs) are recognized as promising electrocatalysts for the oxygen evolution reaction (OER) because of their permanent porosity and rich architectural diversity; however, ionic MOFs enabling fast ions exchange during OER are rarely explored. Here, an ionic MOF (Ni-btz) constructed with an azolate ligand is selected, and continuous 3D bimetallic MOF (NiFe-btz) films deriving from high-degree intergrowth of microsized MOFs particles are fabricated. The as-prepared NiFe-btz/NF-OH electrode exhibits excellent OER performance with a low overpotential of 239 mV at 10 mA cm under alkaline condition.

Study on the Aging Behavior of an Ultra-High Molecular Weight Polyethylene Fiber Barrier Net in a Marine Environment.

In the present work, the performance of ultra-high molecular weight polyethylene (UHMWPE) barrier nets in marine environments is investigated by Fourier transform infrared spectroscopy, thermogravimetry, scanning electron microscopy, and tensile experiments. The chemical, morphological, thermal stability, and strength changes after aging in salt spray, hygrothermal, and ultraviolet (UV) environments are characterized. An environmental spectrum is designed to simulate a real service environment and predict the service life of UHMWPE.

Turning Electronic Waste to Continuous-Flow Reactor Using Porous Aromatic Frameworks.

Extraction of valuable metals such as gold from electronic wastes (e-waste) is regarded as a promising way of environmental remediation; however, this process is still confronted with the cost-ineffective product for normal usages like electronic devices or jewelry. Therefore, there would be merits in directly converting gold from e-waste to materials of higher value, for example, catalysts for pollutant treatment. Herein, a porous aromatic framework (PAF) with cationic sites, named iPAF-7, was synthesized and exhibited rapid extraction of gold from e-waste.

Pyrene-based covalent organic framework for selective enrichment of hydrophobic peptides with simultaneous proteins exclusion.

Owing to the desirable structures, covalent organic frameworks (COFs) have emerged as promising porous crystalline materials in bioanalytical and biomedical science. However, the application of their merits for analysis of hydrophobic peptides in complicated bio-samples has not been well investigated, possibly due to challenges in developing materials with high-specific binding effect of target peptides and accurate controllable pore-size for high selectivity. In this study, we proposed the size-exclusive peptide enrichment with Azo-COF constructed from 1,3,6,8-tetrabromopyrene (TBPy) building block and p-azoaniline linking units.

Spherical V-doped nickel-iron LDH decorated on NiS as a high-efficiency electrocatalyst for the oxygen evolution reaction.

Due to the slow reaction kinetics of the oxygen evolution reaction (OER), the electrolysis rate of water is greatly limited. Therefore, it is of great significance to study stable and efficient non-noble metal based electrocatalysts. In this paper, three-dimensional (3D) spherical V-NiFe LDH@NiS was developed by exquisitely decorating ultra-thin V-doped NiFe layered dihydroxide (NiFe-LDH) on NiS nanosheets supported by nickel foam (NF).

Selenide-based 3D folded polymetallic nanosheets for a highly efficient oxygen evolution reaction.

Electrochemical water splitting, which is considered to be one of the fruitful strategies to achieve efficient and pollution-free hydrogen production, has been deemed as a key technology to achieve renewable energy conversion. Oxygen evolution reaction (OER) is a decisive step in water splitting. Slow kinetics seriously limits the effective utilization of energy thus it is extremely urgent to develop electrocatalysts that can effectively reduce the reaction energy barrier thus accelerate OER kinetics.

Continuous Porous Aromatic Framework Membranes with Modifiable Sites for Optimized Gas Separation.

Continuous microporous membranes are widely studied for gas separation, due to their low energy premium and strong molecular specificity. Porous aromatic frameworks (PAFs) with their exceptional stability and structural flexibility are suited to a wide range of separations. Main-stream PAF-based membranes are usually prepared with polymeric matrices, but their discrete entities and boundary defects weaken their selectivity and permeability.

Regulating the electronic structure of CoMoO microrod by phosphorus doping: an efficient electrocatalyst for the hydrogen evolution reaction.

It is of extreme importance to design efficient electrocatalysts for hydrogen evolution reaction (HER), which is considered as a promising approach to provide efficient and renewable clean fuel (hydrogen). Tuning the electronic structure through heteroatom doping demonstrates one of the most effective strategies to promote the electrocatalytic performance of HER. Herein, phosphorus-doping modulation is utilized to fabricate monoclinic P-CoMoO with optimized electron structure supported on nickel foam (P-CoMoO/NF) for alkaline HER via a facile hydrothermal method, followed by low-temperature phosphidation.

Efficient Gold Recovery from E-Waste via a Chelate-Containing Porous Aromatic Framework.

Extracting gold from wastes of electronic equipment (e-waste) is a sustainable strategy for the recovery of the precious metal, reducing environmental pollution, and addressing the growing demands for gold resources. In this work, we synthesized a thiourea-modified porous aromatic framework (PAF-1-thiourea) with exceptional gold-extraction ability. The optimum adsorption capacity for PAF-1-thiourea to gold reaches up to 2629.

Synergic Catalysts of Polyoxometalate@Cationic Porous Aromatic Frameworks: Reciprocal Modulation of Both Capture and Conversion Materials.

Compositional catalysts based on porous supports and incorporated catalytic nanoparticles have achieved great successes during the past decades. However, rational design of synergic catalysts and modulating the interactions between functional supports and catalytic sites are still far from being well developed. In this work, aiming at overcoming the difficulties of comprehensive screening of porous supports and correspondingly matched catalytic sites, a cationic porous aromatic framework as a capturing platform and polyoxometalate anions as conversion materials are separately designed, and their combination is modularly controlled.

Erosion Failure of a Soil Slope by Heavy Rain: Laboratory Investigation and Modified GA Model of Soil Slope Failure.

Rainfall has been identified as one of the main causes for slope failures in areas where high annual rainfall is experienced. The slope angle is important for its stability during rainfall. This paper aimed to determine the impact of the angle of soil slope on the migration of wetting front in rainfall.

The adsorption and simulated separation of light hydrocarbons in isoreticular metal-organic frameworks based on dendritic ligands with different aliphatic side chains.

Three isoreticular metal-organic frameworks, JUC-100, JUC-103 and JUC-106, were synthesized by connecting six-node dendritic ligands to a [Zn4O(CO2)6] cluster. JUC-103 and JUC-106 have additional methyl and ethyl groups, respectively, in the pores with respect to JUC-100. The uptake measurements of the three MOFs for CH4, C2H4, C2H6 and C3H8 were carried out.

Ammonia capture in porous organic polymers densely functionalized with Brønsted acid groups.

The elimination of specific environmental and industrial contaminants, which are hazardous at only part per million to part per billion concentrations, poses a significant technological challenge. Adsorptive materials designed for such processes must be engendered with an exceptionally high enthalpy of adsorption for the analyte of interest. Rather than relying on a single strong interaction, the use of multiple chemical interactions is an emerging strategy for achieving this requisite physical parameter.

Targeted synthesis of porous aromatic frameworks and their composites for versatile, facile, efficacious, and durable antibacterial polymer coatings.

Novel quaternary pyridinium-type porous aromatic frameworks, PAF-50, and their composites, AgCl-PAF-50, have been synthesized to effectively and efficiently inhibit the growth of bacteria. Most importantly, both PAF-50 and AgCl-PAF-50 have excellent compatibility with conventional polymers, which lead to great operation flexibility and versatility for antibactrial coatings on various medical devices simply via solution or spray coating.

Targeted synthesis of a 2D ordered porous organic framework for drug release.

A novel 2D porous organic framework based on the nucleophilic substitution of cyanuric chloride has been designed and synthesized successfully, which possesses an ordered structure, permanent porosity and drug release ability towards ibuprofen.

A covalently-linked microporous organic-inorganic hybrid framework containing polyhedral oligomeric silsesquioxane moieties.

By a Yamamoto-type of Ullmann cross-coupling reaction, a well-defined covalently-linked microporous organic-inorganic hybrid framework polyoctaphenylsilsesquioxane (JUC-Z1) was effectively prepared from the nano building block p-iodio-octaphenylsilsesquioxane (I8OPS) with a yield of ca. 100%. The structure of JUC-Z1 was characterized by (13)C CP/MAS NMR and (29)Si MAS NMR experiments.

Targeted synthesis of a 3D porous aromatic framework for selective sorption of benzene.

A novel 3D porous aromatic framework (PAF) based on a tetraphenylmethane block and a triangular triazine ring been designed and synthesized, with 1109 m(2) g(-1) Langmuir surface area, and shows selective sorption of benzene.