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Covalent organic frameworks (COFs) are innovative and remarkable crystalline/porous macrocyclic materials that are composed of purely organic building blocks with strong covalent linkages between light atoms. These newly developed crystals with tailor-made constructions have attracted widespread attention due to low density, promising stabilities, great surface area, ordered and regular porous networks, unique functionalities, as well as proper crystallinity. Impressively, in comparison with other giant molecules, these materials are synthetically manageable and fully organizationally pre-designable. The unique features have permitted COFs to be advanced in combination with other materials such as polymeric, metallic, and carbonaceous materials for designing and discovering novel promising systems in numerous utilizations. Herein, this review highlights the advancement of COF hybrid-based materials for diverse industrial applications. First, a summary of the latest achievements of COFs in various fields is presented, and then hybrids of these materials and their unique applications are considered.

A simple, yet efficient synthetic approach for the construction of vinylene-linked conjugated porous networks was developed. Based on the Horner–Wadsworth–Emmons reaction, the condensation polymerization for the formation of an sp2 carbon-linkage can be achieved at room temperature. The resulting vinylene-linked frameworks exhibit a promising porous nature with the best surface area of up to 1373 m2 g−1. Their intrinsic conjugated architectures and semiconducting properties lead to photocatalytic evolution of hydrogen from water under visible light irradiation. This new synthesis method provides a facile means to prepare attractive sp2 carbon linked porous organic frameworks.

Herein, we present a rational strategy for the development of π-electron-enriched conjugated microporous polymers (CMPs) under mild conditions, aiming for the super-adsorption of iodine. Among them, TBTT-CMP@1 exhibits a superior iodine uptake up to 442 wt%. In addition, TBTT-CMP@3 displays outstanding CO2 adsorption capacity with uptake up to 1578 mg g−1 under 70 bar and 318 K conditions.

Tremendous efforts have been made to achieve the ordered porosity of solids. Nowadays, researchers are developing strategies for the preparation of uniformly porous carbons derived from sustainable precursors, such as biomass. Ordered and/or uniform interconnected porosity in carbons improves the mass transfer of various species in porous networks, which is especially favorable for adsorption, catalysis, and energy storage/conversion-related applications. This review presents advancements, challenges and prospects in the relatively new field of biomass-derived carbons with ordered porosity, which is an attractive topic for scientists and engineers studying materials science, chemical engineering, environmental science, and more. Particularly, it is addressed to researchers who are interested in the design and synthesis of nanomaterials for solving the challenging energy and environmental issues.

Selective sensing of biothiols holds immense importance due to the adverse roles of abnormal concentrations of biothiols in several diseases, henceforth demanding widespread research for developing a sensory receptor towards the selective detection of biothiols. Herein the designed synthesis of a simple 3D porous coordination polymer, PCP-1 has been carried out following a conventional solvothermal reaction route that shows selective sensing of biothiols (Cys & Hcy) at the nanomolar level with a very short response time carrying enormous importance for simplistic biological studies. Due to the presence of paramagnetic metal centres, MnII-MOF itself remains in a quenched state that shows selective “turn-on” fluorescence response in the presence of electron-rich biothiols which was thoroughly studied by DFT. In continuation, the sensor PCP-1 was equally responsive in different biological matrices such as fresh bovine serum and human urine showing the bio-applicability of the porous network which is of immense importance in analytical domains in the modern era. Thus, the detection of biothiols from human urine would be enormously helpful in preparing a paediatric reference range for clinical use. As a result, the detection of either cystinuria or homocystinuria in patients will be done with ease. Additionally, PCP-1 has selective adsorption capability of CO2 over N2 at low temperature with the aid of the size-exclusion effect of interstitial channels along with the dipole–induced dipole interaction. The magnetic properties of the framework, PCP-1 indicate weak anti-ferromagnetic coupling between the MnII centres of the trinuclear building block. These two hidden potentials may be properly utilised in the domain of GHG mitigating agents and spintronic applications, respectively.

The creation of molecular or colloidal building blocks which can self-assemble into complex, ordered porous structures has been long sought-after, and so are the guiding principles behind this creation. The pursuit of this goal has led to the creation of novel classes of materials like metal organic frameworks (MOFs) and covalent organic frameworks (COFs). In theory, a tremendous number of structures can be formed by these materials due to the variety of geometries available to their building blocks. However, most realized crystal structures tend to be simple or homoporous and typically assemble from building blocks with high degrees of symmetry. Building blocks with low degrees of symmetry suitable for assembly into the more complex structures tend to assemble into polymorphous or disordered structures instead. In this work, we use Monte Carlo simulations of patchy vertex-like building blocks to show how the addition of chemical specificity via orthogonally reacting functional sites can allow vertex-like building blocks with even asymmetric geometries to self-assemble into ordered crystallites of various complex structures. In addition to demonstrating the utility of such a strategy in creating ordered, heteroporous structures, we also demonstrate that it can be used as a means for tuning specific features of the crystal structure, accomplishing such aims as the control of relative pore sizes. We also discuss heuristics for properly designing molecules so that they can assemble into target structures.

Slippery lubricant-infused porous surfaces (SLIPS), which typically rely on surface structure and chemical properties to store and maintain the lubricant, usually lack fast self-replenishing ability due to the limited storage capacity of the lubricant or structure obstruction to fluid flow. Here, a practical and dexterous strategy for creating a lubricant-infused fibrous porous surface (LIFPS) which combines ultra-large capacity with fast self-replenishment is reported. This capability stems from the well-designed internal and surface hierarchical microstructures. Regularly arranged cavities designed to store the lubricant, similar to the nectaries of Nepenthes, are embedded inside the material and interconnected by a 3D fibrous porous network to promote rapid circulation of the lubricant. The internal pore structure and surface are interconnected by a 3D network of fibrous fine pores, and thereby form the surface microstructure, which effectively controls the leakage of the internal lubricant and maintains the stability of the surface lubricant film. Surface damage test shows that it is suitable for rapid healing of surface properties. This novel structural design, preparation method and the resulting surfaces are critical for designing advanced and fast self-replenishing slippery surfaces and driving their application.

Microporous networks based on boronate ester-capped iron(ii) clathrochelate complexes are described. The networks were obtained by covalent cross-linking of tetrabrominated clathrochelate complexes via Suzuki-Miyaura polycross-coupling reactions with diboronic acids, or by Sonogashira-Hagihara polycross-coupling of clathrochelate complexes with terminal alkyne functions and 1,3,5-tribromobenzene. The networks display permanent porosity with apparent Brunauer-Emmett-Teller surface areas of up to SABET = 593 m2 g-1. A clathrochelate complex based on an enantiopure dioximato ligand was used to prepare chiral networks. One of these networks was shown to preferentially absorb d-tryptophan over l-tryptophan.

Porous carbons are promising materials for supercapacitor electrodes owing to their excellent electrical conductivity, high surface area, unique porous networks, and superior chemical inertness. This article summarizes the recent development of block copolymer-based porous carbons for supercapacitor electrodes. We first introduce the fundamentals of supercapacitors and block copolymers, followed by representative examples to highlight the use of block copolymers for fabricating porous carbons that have morphologies unattainable by other strategies. Instead of a comprehensive review, the article surveys papers published within the past five years. We discuss block copolymer-based porous carbons in the formats of zero-dimensional powders, one-dimensional fibers, two-dimensional films, and three-dimensional monoliths. In the end, the article presents a few challenges and opportunities associated with the application of block copolymers for supercapacitors.

Superhydrophobic films that are simple, inexpensive, corrosion-resistant and multifunctional are in high demand for industrial applications. We propose a simple and economical phase separation method for fabricating superhydrophobic films using polylactic acid (PLA), nano-SiO2 and a mixture of good and poor solvents to construct a rough surface with a nano/microstructured morphology. The phase separation-induced superhydrophobic PLA/SiO2 composite film with a porous network structure has a water contact angle greater than 164°. This method can be applied to a variety of surfaces or used in large-scale industrial production. The fabricated superhydrophobic films may be applied in biological fields because PLA is a good biodegradable material.

A novel strategy for producing three-dimensional (3D) porous Ti3C2Tx(MXene) networks by alkali-induced crumpling of Ti3C2Txnanosheets is presented. These networks display high capacity and good rate performance as anode materials for sodium-ion batteries.

Nano-functional materials with 3D porous architectures have gained increasing importance due to their potential applications deriving from outstanding physical and chemical reaction properties. It is still a long-standing challenge to assemble organic energetic molecules and their composites into functional macroscale architectures with porous networks for practical applications. Herein, we introduce a general approach for constructing 3D architectures (sizes in dozens of millimeters) with a porous network of energetic molecules through the two-step self-assembly of energetic nanoparticles, which involves electrostatic interactions and micro-crystallization on interfaces of nanoparticles driven by an ice-template process. 3D porous architectures of several typical energetic molecules were successfully prepared to further illustrate the effectiveness of this approach. The significantly enhanced chemical reactivity induced by thermal and shock stimuli contributed to 3D architectures with hierarchical pore network. This study demonstrates the potential of the controlled preparation of organic energetic materials with 3D porous architecture, which meets a wide range of applications on optimization of physical and chemical properties.

Porous bioglass (BG) scaffolds are of great importance in tissue engineering because of their excellent osteogenic properties for bone regeneration. Herein, we reported for the first time the use of amino-modified bacterial cellulose (NBC) as a template to prepare a three-dimensional (3D) nanofibrous BG scaffold by a facile modified sol–gel approach under ultrasonic treatment. The results suggested that the amino groups on the BC template could effectively promote the absorption of the deposited CaO and SiO2 precursors, and the as-obtained BG scaffold showed a 3D interconnected porous network structure consisting of nanofibers with a diameter of about 20 nm. Furthermore, the as-obtained BG scaffold showed very good bioactivity after being immersed in SBF for 7 days. This research provides a facile and efficient way to prepare a nanofibrous BG scaffold with 3D porous structure, which can be used as a promising candidate for biomedical applications.

From the interplay between high-resolution scanning tunneling microscopy imaging/manipulations and density functional theory calculations, we display the hierarchical formation of supramolecular networks by codeposition of 9eG molecules and Fe atoms on Au(111) based on the flexible coordination bonds (the adaptability and versatility in the coordination modes). In the first step, homochiral islands composed of homochiral G4Fe2 motifs are formed; and then in the second step, thermal treatment results in the transformation into the porous networks composed of heterochiral G4Fe2 motifs with the ratio of the components being constant. In situ STM manipulations and the coexistence of some other heterochiral G4Fe2 motifs and clusters also show the flexibility of the coordination bonds involved. These studies may provide a fundamental understanding of the regulations of multilevel supramolecular structures and shed light on the formation of designed supramolecular nanostructures.

We report internally porous Au-embedded hematite on FTO using CTAB. Incorporation of Au and CTAB synergistically improved the photocurrent of hematite by 63% at 1.23 VRHE in 1 M NaOH under standard illumination conditions. The performance enhancement is due to the increased donor density and optical properties of internally porous networks and plasmonic absorption of hematite.

Hypercrosslinked polymers for selective CO2 capture have been successfully synthesized from highly rigid contorted blocks via a low-cost versatile strategy. Such amorphous materials with improved porosities achieve high specific surface areas of up to 1616 m2 g−1 and substantially improved pore volumes (1.53 cm3 g−1). The polymer networks feature hierarchically porous structures ranging from ultramicropores to mesopores (0.50 to 3.80 nm) as well as high physicochemical stability. They can uptake 15.9 wt% CO2 at 273 K/1 bar, surpassing nearly all polymers of intrinsic microporosity (PIMs) and most known hypercrosslinked polymers (HCPs). The abundant ultramicropores with pore diameters centered at around 0.50 nm allow selective CO2 uptake against N2 (ideal selectivity: 69.7) and CH4 (15.8). These results are significant for molecular design and emphasize the importance of utilizing rigid contorted blocks to build hierarchically porous networks for effective CO2 capture applications.

This paper is derived from my ‘closing remarks’ lecture at the 287th Faraday Discussions meeting on New Directions in Porous Crystalline Materials, Edinburgh, UK, 5–7 June, 2017. This meeting comprised sessions on the design of porous networks, and their capture, storage, separation, conducting properties, catalysts, resistance to chemicals and moisture, simulation, and electronic structures. This paper details the achievements and developments in the field, as reflected in invited speakers’ papers and discussions with the attendees during the meeting.

Three-dimensional (3D) carbon-based architectures with their macroscopic monolithic shapes, well-defined interconnected porous networks, large surface areas and excellent adsorption capacities have received extensive attention in the field of environmental remediation. Given the frequent occurrence of oil spills, the demand for 3D carbon materials for oil remediation has increased very rapidly in recent years; however, considerable synthesis and functionalization studies remain to be performed to fully exploit their applications. This review aims to give an overview of the synthesis, modification and functionalization of 3D carbon-based architectures for oil remediation. In particular, we highlight novel monolithic materials with multifunctions such as photocatalytic activity, which can not only play a role as adsorbents but can also photocatalytically degradate oil.

Hyperpolarization of metabolites by dissolution dynamic nuclear polarization (D-DNP) for MRI applications often requires fast and efficient removal of the radicals (polarizing agents). Ordered mesoporous SBA-15 silica materials containing homogeneously dispersed radicals, referred to as HYperPolarizing SOlids (HYPSOs), enable high polarization – P(1H) = 50% at 1.2 K – and straightforward separation of the polarizing HYPSO material from the hyperpolarized solution by filtration. However, the one-dimensional tubular pores of SBA-15 type materials are not ideal for nuclear spin diffusion, which may limit efficient polarization. Here, we develop a generation of hyperpolarizing solids based on a SBA-16 structure with a network of pores interconnected in three dimensions, which allows a significant increase of polarization, i.e. P(1H) = 63% at 1.2 K. This result illustrates how one can improve materials by combining a control of the incorporation of radicals with a better design of the porous network structures., Chemical Science, 7 (11), ISSN:2041-6520, ISSN:2041-6539

Designed porous copper hexacyanoferrate micro-capsule beads (CuHCF-MCB) were prepared using freeze-drying (FD). Multi-scale porous networks composed of Angstrom, nanometer, and micrometer sizes were obtained in the desired shapes using a simple drying process. They provide special benefits such as fast kinetics and high capacity. The Cs adsorption equilibrium and kinetics fit the pseudo-second-order kinetic model well. The adsorption rate of FD-CuHCF-MCB was improved to about 15 times higher than that of the heat-drying process because of the highly multi-scale porous structure of FD-CuHCF-MCB, which facilitated solution flow and rapid ion-diffusion inside the MCB.

Novel low-dimensional metal–organic structures incorporating heavy metal Pb atoms as coordination centres are formed on a Au(111) surface by means of on-surface metallo-supramolecular assembly. The molecular building blocks are porphyrin derivatives functionalized with pyridyl groups. These building blocks are linked via a unique pyridyl–Pb–pyridyl coordination motif that does not exist in conventional coordination chemistry but emerges on the surface. The Pb atoms are coordinated in structures of distinctive morphologies, including one-dimensional single chains, double-chains and ladders, and two-dimensional porous networks, owing to the specific sites of the pyridyl groups in the molecular building blocks.

Palladium nanoparticles supported on N-doped hierarchically porous carbon, Pd/CNx, has been developed as a highly efficient, reusable and environmentally benign heterogeneous catalyst for the selective hydrogenation of various α,β-unsaturated carbonyls to their corresponding saturated carbonyls under mild conditions (303 K, 1 bar H2). Complete conversion of a series of α,β-unsaturated carbonyls was achieved with excellent selectivity (>99%) within 4 h. Moreover, the catalyst can be easily recovered by centrifugation and withstands recycling up to 8 times without apparent loss of activity and selectivity. The considerable catalytic performance is attributed to the hierarchically porous network and incorporation of nitrogen atoms. This catalytic system opens up an efficient, selective, recyclable and sustainable method for selective hydrogenation.

Self-assembly of the tripyridyl ligand 2,4,6-tris(4-pyridyl)triazine(TPT) and ZnI2via the gas phase produced three kinds of networks: [(ZnI2)(TPT)]n; [(ZnI2)3(TPT)2]n; and [(ZnI2)(μ-I)(ZnI)(TPT)]n. [(ZnI2)3(TPT)2]n is the first example of the single crystal formation of a porous network via the gas phase and showed the dependence of iodine encapsulation on the crystal size.

A calixarene-based supramolecular hydrogel with a porous network structure was successfully constructed via a hierarchical induced assembly strategy, showing reversible or irreversible gelation behaviors in response to several external stimuli including thermal, redox and ionic strength.

Mother Nature has always taught us lots about the arcanum of God's creation, which primarily ties to the wonderful and complex self-assembly of biomolecules even in a mild condition. In the present work, we put forward a bio-inspired strategy, that is, directly bring in biological systems capable of self-assembly to fabricate functionalized hierarchical structures for effective gas sensing. For advanced pollination, biomolecules in pollen coats could self assemble to form bio-structures with effective mass transportablity, and herein were used to guide the self assembly of SnO2-precusors, which finally transferred to SnO2 materials by calcination. Gaining the 3D hierarchical porous structrues formed in the self-assembly of biomolecules, the as-fabricated SnO2 has high connective porous networks from macro- to micro-, and even nanoscale. The specific structures could facilite target gases to quickly transport towards, and then fully react with, the SnO2 nanoparticles, and thus endow the SnO2 with excellent gas response to both reducing gases (C2H5OH and CH3CH2CH3) and oxidising gas (Cl2). This present strategy provides a novel and facile way towards the development of functionallized hierarchical structures by learning from natural self-assembled systems. The resultant hierarchical structures can be extended to other applications in filters, adsorbents, catalysis, thermal, acoustic and electrical insulators, and so on.

The design and fabrication of three-dimensional multifunctional architectures from the appropriate nanoscale building blocks, including the strategic use of void space and deliberate disorder as design components, permits a re-examination of devices that produce or store energy as discussed in this critical review. The appropriate electronic, ionic, and electrochemical requirements for such devices may now be assembled into nanoarchitectures on the bench-top through the synthesis of low density, ultraporous nanoarchitectures that meld high surface area for heterogeneous reactions with a continuous, porous network for rapid molecular flux. Such nanoarchitectures amplify the nature of electrified interfaces and challenge the standard ways in which electrochemically active materials are both understood and used for energy storage. An architectural viewpoint provides a powerful metaphor to guide chemists and materials scientists in the design of energy-storing nanoarchitectures that depart from the hegemony of periodicity and order with the promise--and demonstration--of even higher performance (265 references).

New sol–gel derived silicas made with a double porous network with pore sizes on two very different length scales (typically several nm and several µm) are reproducibly synthesised using molecular 2,3-di-n-decyloxyanthracene (DDOA) organogelators. The micron sized fibrous patterns made in methanol by DDOA aggregates are used as a blueprint for the growing of porous silica fibres. At the same time the mesoporous silica network seems to be templated by smaller DDOA aggregates. By varying the DDOA concentration, the mean size of the mesoporous network increases from 50 to 120 A and the pore shape changes from a ink-bottle to a cylindrical type.

Two new three-dimensional (3D) porous structures based on the mixed flexible and rigid organic ligands, [Cd1.5(bmip)(tpa)1.5(DMF)1.5]n (1) and [Co1.5(bmip)0.5(bpdc)1.5(DMF)2]n (2) (bmip = 1,3-bis(2-methylimidazolyl)propane, H2tpa = terephthalic acid, H2bpdc = biphenyl-4,4′-dicarboxylic acid, DMF = N,N-dimethylformamide) have been prepared under solvothermal conditions. Complex 1 contains a trinuclear Cd unit, in which the trinuclear Cd cluster acts as an eight-connected node with two pairs of flexible bmip and six rigid tpa ligands. Complex 2 exhibits a two-fold interpenetrated porous network based on a trinuclear Co cluster as eight-connected vertices with two flexible bmip and six rigid tpa ligands. Both 1 and 2 show selective gas adsorption of CO2 over N2 and H2. Furthermore, complex 1 displays an uncommon CO2 adsorption isotherm and hysteretic desorption behaviors at 195 K.

The control over the formation of a bi-component porous network was attained by the self-assembly at a solid-liquid interface by exploiting both primary and secondary non-covalent interactions between melamine and N(3)-alkylated xanthine modules.

An unprecedented organic-inorganic hybrid germanoniobate compound Na4[Cu(en)2(H2O)2]5[Na6Ge8Nb32O108H8(OH)4]·41H2O (1) was synthesized under the hydrothermal condition. In compound 1, the {Nb16} cage containing four {GeO4} tetrahedra in its internal cavity results in a heteropolyniobate anion [H4Ge4Nb16O54(OH)2](10-) ({Ge4Nb16}), which is connected by a {Na6} cluster into the first germanoniobate-based sandwich-type structure. Further, the sandwich germanoniobates are connected by [Na2Cu(en)2O6H8] groups into a porous network with one dimensional channels along the a-axis. Photocatalytic study reveals that compound 1 exhibits good photocatalytic activity for the degradation of methylene blue.

A new class of advanced porous network structured carbon materials exhibits very attractive capacitive properties when utilized as electrodes for organic electrolyte supercapacitors, including large capacitances up to 210 F g−1, unusually high energy densities of 21.4–41.8 W h kg−1 at power densities of 67.5–10 800 W kg−1, and excellent cycling stability.

An interesting diversity of linkage types — weak covalent, hydrogen bonding, and Ag⋯π interactions — is shown to be involved in the 3D porous network formed by the title compound.

Mesoporous silica nanomaterials are a novel class of materials that offer a highly complex porous network with nanometre-sized channels into which a wide amount of differently sized guests can be incorporated. This makes them an ideal host for various applications for example in catalysis, chromatography and nanomedicine. For these applications, analyzing the host properties and understanding the complicated host-guest interactions is of pivotal importance. In this perspective we review some of our recent work that demonstrates that single molecule microscopy techniques can be utilized to characterize the porous silica host with unprecedented detail. Furthermore, the single molecule studies reveal sample heterogeneities and are a highly efficient tool to gain direct mechanistic insights into the host-guest interactions. Single molecule microscopy thus contributes to a thorough understanding of these nanomaterials enabling the development of novel tailor-made materials and hence optimizing their applicability significantly.

An automated method has been developed to fully characterize the three-dimensional structure of zeolite porous networks. The proposed optimization-based approach starts with the crystallographic coordinates of a structure and identifies all portals, channels, and cages in a unit cell, as well as their connectivity. We apply our algorithms to known zeolites, hypothetical zeolites, and zeolite-like structures and use the characterizations to calculate important quantities such as pore size distribution, accessible volume, surface area, and largest cavity and pore limiting diameters. We aggregate this data over many framework types to gain insights about zeolite selectivity. Finally, we develop a continuous-time Markov chain model to estimate the probability of occupancy of adsorption sites throughout the porous network. ZEOMICS, an online database of structure characterizations and web tool for the automated approach is freely available to the scientific community (http://helios.princeton.edu/zeomics/).

International audience; A new host compound TTPP (tris(2,3-triphenylenedioxy)cyclotriphosphazene), which is able to form a porous network, has been synthesized in five steps. When it crystallizes as a single component, TTPP exhibits a crystal structure with a monoclinic unit cell, the space group P21/c (no. 14) and unit cell dimensions of a 1⁄4 14.909(2) A#, b 1⁄4 31.013(4) A#, c 1⁄4 9.074(1) A#, b 1⁄4 102.12(1) . Co-crystallization of TTPP with 1,2,4-trichlorobenzene forms an inclusion crystal having a triclinic unit cell with a P"1 space group (no. 2) and unit cell dimensions of a 1⁄4 8.769(2) A#, b 1⁄4 15.024(2) A#, c 1⁄4 21.216(2) A#, a 1⁄4 94.82 (0) , b 1⁄4 99.98(0) , g 1⁄4 98.23(1). The guest lies in two kinds of channel-like cavities with dimensions of 6.1 8.4 A#2 and 10.7 12.4 A#2 respectively. This represents the biggest porous network built up by spirocyclotriphosphazene derivatives to date.

An equimolar mixture of two structurally related molecular building blocks self-assembles into a 2D non-crystalline bimolecular porous pattern at a liquid-solid interface as revealed by scanning tunneling microscopy.

An analysis is made of the equilibrium partitioning of macromolecules between a random porous network and a bulk liquid. For porous material, a randomly embedded model is employed, in which the solid phase is defined as the region occupied by the solid phase elements randomly placed in space. Three typical solid phase elements are considered, i.e., sphere, rod and flexible chain. A simple formula is obtained for the equilibrium partition coefficient σ of rigid macromolecules. It is found that the molecular size dependence of σ is quite different for the three solid phase elements. An approximate, but plausible expression for σ is also obtained for the linear flexible chain.