Solvent-Induced Self-Assembly Strategy to Synthesize Well-Defined Hierarchically Porous Polymers

Blue Laser Triggered Hemostatic Peptide Hydrogel for Gastrointestinal Bleeding Treatment

In an emergency, nonvariceal upper gastrointestinal bleeding (NVUGIB), endoscopic hemostasis is considered the gold standard intervention. However, current endoscopic hemostasis is very challenging to manage bleeding in large-diameter or deep lesions highly prone to rebleeding risk. Herein, a novel hemostatic peptide hydrogel (HPH) is reported, consisting of a self-assembly peptide sequence CFLIVIGSIIVPGDGVPGDG (PFV) and gelatin methacryloyl (GelMA), which can be triggered by blue laser endoscopy (BLE) for nonvariceal upper gastrointestinal bleeding treatment without recurring bleeding concerns. Upon contact with GelMA solution, PFV immediately fibrillates into β-sheet nanofiber and solvent-induced self-assembly to form HPH gel. HPH nanofiber networks induced ultrafast coagulation by enveloping blood cells and activating platelets and coagulation factors even to the blood with coagulopathy. Besides its remarkable hemostatic performance in artery and liver injury models, HPH achieves instant bleeding management in porcine NVUGIB models within 60 s by preventing the rebleeding risk. This work demonstrates an extraordinary hemostatic agent for NVUGIB intervention by BLE for the first time, broadening potential application scenarios, including patients with coagulopathy and promising clinical prospects.

Chemically tailored block copolymers for highly reliable sub-10-nm patterns by directed self-assembly

While block copolymer (BCP) lithography is theoretically capable of printing features smaller than 10 nm, developing practical BCPs for this purpose remains challenging. Herein, we report the creation of a chemically tailored, highly reliable, and practically applicable block copolymer and sub-10-nm line patterns by directed self-assembly. Polystyrene-block-[poly(glycidyl methacrylate)-random-poly(methyl methacrylate)] (PS-b-(PGMA-r-PMMA) or PS-b-PGM), which is based on PS-b-PMMA with an appropriate amount of introduced PGMA (10-33 mol%) is quantitatively post-functionalized with thiols. The use of 2,2,2-trifluoroethanethiol leads to polymers (PS-b-PGFMs) with Flory-Huggins interaction parameters (χ) that are 3.5-4.6-times higher than that of PS-b-PMMA and well-defined higher-order structures with domain spacings of less than 20 nm. This study leads to the smallest perpendicular lamellar domain size of 12.3 nm. Furthermore, thin-film lamellar domain alignment and vertical orientation are highly reliably and reproducibly obtained by directed self-assembly to yield line patterns that correspond to a 7.6 nm half-pitch size.

A Versatile Synthesis Platform Based on Polymer Cubosomes for a Library of Highly Ordered Nanoporous Metal Oxides Particles

Polymer cubosomes (PCs) have well-defined inverse bicontinuous cubic mesophases formed by amphiphilic block copolymer bilayers. The open hydrophilic channels, large periods, and robust physical properties of PCs are advantageous to many host-guest interactions and yet not fully exploited, especially in the fields of functional nanomaterials. Here, the self-assembly of poly(ethylene oxide)-block-polystyrene block copolymers is systematically investigated and a series of robust PCs is developed via a cosolvent method. Ordered nanoporous metal oxide particles are obtained by selectively filling the hydrophilic channels of PCs via an impregnation strategy, followed by a two-step thermal treatment. Based on this versatile PC platform, the general synthesis of a library of ordered porous particles with different pore structures3 ¯ $\bar{3}$ 3 ¯ $\bar{3}$ , tunable large pore size (18-78 nm), high specific surface areas (up to 123.3 m2 g-1 for WO3) and diverse framework compositions, such as transition and non-transition metal oxides, rare earth chloride oxides, perovskite, pyrochlore, and high-entropy metal oxides is demonstrated. As typical materials obtained via this method, ordered porous WO3 particles have the advantages of open continuous structure and semiconducting properties, thus showing superior gas sensing performances toward hydrogen sulfide.

Highly branched and ultrathin Au nanodendrites for reduction catalysis

Two-dimensional (2D) materials have garnered significant attention due to their distinctive physicochemical properties, with 2D noble metal nanodendrites being particularly intriguing in terms of their properties and functional prospects. However, the synthesis of ultrathin and highly branched gold nanodendrites (AuNDs) still poses challenges. In this study, we successfully achieved the synthesis of highly branched 2D AuNDs with a thickness of 4 nm by employing a carboxyl-functionalized C22-tailed surfactant along with the co-directing agent 2-mercaptonicotinic acid (2-MNA). The careful selection of specific thiol molecules such as 2-MNA is crucial for controlling the degree of branching and promoting the formation of ultrathin nanodendrites. Furthermore, we extended this method to synthesize alloy nanodendrites (AuAg NDs and AuCoAg NDs) using a similar approach. Due to their highly branched and ultrathin two-dimensional morphology, these prepared AuNDs exhibit excellent catalytic performance in the model reaction for 4-NP reduction. This thiol-induced synthesis strategy for AuNDs opens up new possibilities for designing other Au nanomaterials with an ultrathin morphology/structure.

In situ injectable thermoresponsive nanocomposite hydrogel based on hydroxypropyl chitosan for precise synergistic calcium-overload, photodynamic and photothermal tumor therapy

Traditional therapies have poor accuracy and significant toxic side effects in the process of tumor treatment. The non-traditional treatment methods with high accuracy and efficacy are worth exploring and investigating. Herein, a strategy that enables precise and synergistic therapies of calcium-overload, photodynamic, and photothermal through facile near infrared (NIR) irradiation was carried out base on the injectable and self-healable hydrogel encapsulating indocyanine green (ICG)-loaded and bovine serum albumin (BSA)-modified calcium peroxide (CaO2) nanoparticles (ICG@CaO2-BSA NPs) and bismuth sulfide (Bi2S3) nanorods. The hydrogel fabricated through the dynamic Schiff-base bonds between hydroxypropyl chitosan (HPCS) and aldehyde-modified Pluronic F127 (F127-CHO) as the delivery substrate for functional substances could adhere and grip tumor tissues due to the adhesion of hydroxyl groups in HPCS and the hydrophobic aggregation caused by thermoresponsiveness of F127-CHO. CaO2 in ICG@CaO2-BSA NPs decomposed in the tumor micro-acidic environment to produce calcium ions (Ca2+) and hydrogen peroxide (H2O2), while ICG generated reactive oxygen species (ROS) under NIR irradiation, the photothermal effect of Bi2S3 nanorods and ICG under NIR irradiation could increase the temperature of tumor tissues and ultimately achieve precise tumor cell destruction. Therefore, this strategy will provide promising prospects for precise and efficient treatment of tumors.

Porous Organic Polymers as Active Electrode Materials for Energy Storage Applications

Eco-friendly and efficient energy production and storage technologies are highly demanded to address the environmental and energy crises. Porous organic polymers (POPs) are a class of lightweight porous network materials covalently linked by organic building blocks, possessing high surface areas, tunable pores, and designable components and structures. Due to their unique structural and compositional advantages, POPs have recently emerged as promising electrode materials for energy storage devices, particularly in the realm of supercapacitors and ion batteries. In this work, a comprehensive overview of recent progress and applications of POPs as electrode materials in energy storage devices, including the structural features and synthesis strategies of various POPs, as well as their applications in supercapacitors, lithium batteries, sodium batteries, and potassium batteries are provided. Finally, insights are provided into the future research directions of POPs in electrochemical energy storage technologies. It is anticipated that this work can provide readers with a comprehensive background on the design of POPs-based electrode materials and ignite more research in the development of next-generation energy storage devices.

Polymerization Induced Microphase Separation for the Fabrication of Nanostructured Materials

Polymerization induced microphase separation (PIMS) is a strategy used to develop unique nanostructures with highly useful morphologies through the microphase separation of emergent block copolymers during polymerization. In this process, nanostructures are formed with at least two chemically independent domains, where at least one domain is composed of a robust crosslinked polymer. Crucially, this synthetically simple method is readily used to develop nanostructured materials with the highly coveted co-continuous morphology, which can also be converted into mesoporous materials by selective etching of one domain. As PIMS exploits a block copolymer microphase separation mechanism, the size of each domain can be tightly controlled by modifying the size of block copolymer precursors, thus providing unparalleled control over nanostructure and resultant mesopore sizes. Since its inception 11 years ago, PIMS has been used to develop a vast inventory of advanced materials for an extensive range of applications including biomedical devices, ion exchange membranes, lithium-ion batteries, catalysis, 3D printing, and fluorescence-based sensors, among many others. In this review, we provide a comprehensive overview of the PIMS process, summarize latest developments in PIMS chemistry, and discuss its utility in a wide variety of relevant applications.

Preparation and Magnetic Manipulation of Fe3O4/Acrylic Resin Core-Shell Microspheres

Core-shell microspheres refer to duo-layer or multilayer microspheres, which are widely used in drug delivery, microreactors, etc. Accurate manipulation of microspheres is a research hot spot, while traditional manipulation methods including ultrasonic manipulation and laser manipulation still face some limitations. In this study, magnetic core-shell microspheres were adopted to realize the accurate manipulation of microspheres. Combined with microfluidic technology, polystyrene sulfonic acid (PSSA)/Fe3O4 magnetic fluid was utilized as the core material and photosensitive acrylic resin became the shell material. After UV curing, a magnetic core-shell microsphere with an average size of 55 μm could be achieved, and the diameter was uniform and controllable. By adjusting the flow rate of the dispersed phase, the dual-core microspheres with different core particle sizes that ranged from 9.3 to 28.4 μm could be prepared. Experimental results showed that the prepared Fe3O4/acrylic resin core-shell microspheres can be used as functionalized microspheres that have good magnetic response properties and self-assembly ability. In addition, the magnetic manipulation and self-assembly of the prepared core-shell microspheres were presented with different external magnetic fields. The magnetic core-shell microspheres have shown great potential in the fields of biomedical engineering and targeted delivery of drugs.

Yolk@Wrinkled-double shell smart nanoreactors: new platforms for mineralization of pharmaceutical wastewater

Nanomaterials with "yolk and shell" "structure" can be considered as "nanoreactors" that have significant potential for application in catalysis. Especially in terms of electrochemical energy storage and conversion, the nanoelectrode has a large specific surface area with a unique yolk@shell structure, which can reduce the volume change of the electrode during the charging and discharging process and fast ion/electron transfer channels. The adsorption of products and the improvement of conversion reaction efficiency can greatly improve the stability, speed and cycle performance of the electrode, and it is a kind of ideal electrode material. In this research, heterojunction nanoreactors (FZT Y@WDS) Fe3O4@ZrO2-X@TiO2-X were firstly synthesized based on the solvothermal combined hard-template process, partial etching and calcination. The response surface method was used to determine the performance of the FZT Y@WDS heterojunction nanoreactors and the effects of four process factors: naproxen concentration (NAP), solution pH, the amount of charged photocatalyst, and the irradiation time for photocatalytic degradation of NAP under visible light irradiation. To maximize the photocatalytic activity, the parameters of the loaded catalyst, the pH of the reaction medium, the initial concentration of NAP, and the irradiation time were set to 0.5 g/L, 3, 10 mg/L, and 60 min, respectively, resulting in complete removal of NAP and the optimum amount was calculated to be 0.5 g/L, 5.246, 14.092 mg/L, and 57.362 min, respectively. Considering the promising photocatalytic activity of FZT Y@WDS under visible light and the separation performance of the nanocomposite, we proposed this photocatalyst as an alternative solution for the treatment of pharmaceutical wastewater.

Highly Efficient Capture of Heavy Metal Ions on Amine-Functionalized Porous Polymer Gels

Porous polymer gels (PPGs) are characterized by inherent porosity, a predictable structure, and tunable functionality, which makes them promising for the heavy metal ion trap in environmental remediation. However, their real-world application is obstructed by the balance between performance and economy in material preparation. Development of an efficient and cost-effective approach to produce PPGs with task-specific functionality remains a significant challenge. Here, a two-step strategy to fabricate amine-enriched PPGs, NUT-21-TETA (NUT means Nanjing Tech University, TETA indicates triethylenetetramine), is reported for the first time. The NUT-21-TETA was synthesized through a simple nucleophilic substitution using two readily available and low-cost monomers, mesitylene and α, α′-dichloro-p-xylene, followed by the successful post-synthetic amine functionalization. The obtained NUT-21-TETA demonstrates an extremely high Pb2+ capacity from aqueous solution. The maximum Pb2+ capacity, qm, assessed by the Langmuir model was as high as 1211 mg/g, which is much higher than most benchmark adsorbents including ZIF-8 (1120 mg/g), FGO (842 mg/g), 732-CR resin (397 mg/g), Zeolite 13X (541 mg/g), and AC (58 mg/g). The NUT-21-TETA can be regenerated easily and recycled five times without a noticeable decrease of adsorption capacity. The excellent Pb2+ uptake and perfect reusability, in combination with a low synthesis cost, gives the NUT-21-TETA a strong potential for heavy metal ion removal.

Layer-By-Layer Synthesis of the pH-Responsive Hollow Microcapsule and Investigation of Its Drug Delivery and Anticancer Properties

Multilayered pH-responsive hollow microcapsules with non-toxicity and biological specificity advantages were prepared from two kinds of polymers i.e., chitosan (CH) and poly (ethylene glycol dimethacrylate-co-methacrylic acid) (PE) via layer-by-layer (LbL) method, which is followed by subsequent removal of silica core. The hollow nature of obtained spherical microcapsules was found by transmission electron microscopy (TEM). The microcapsules were prepared as gemcitabine (GM) and curcumin (CR) carriers. The drugs have been loaded within the microcapsules during or after the synthetic procedure. Although acceptable loading efficiencies (LE) were obtained in both methods, the amount of drug loaded during the synthesis method is relatively higher. Values above 78% and 87%, for releasing efficiency (RE%) and encapsulation efficiency (EE%), respectively, demonstrate the high potential of the prepared microcapsules for drug delivery. In addition, the difference between the amount of drug released in acidic and neutral pH indicates the pH-responsivity of the prepared microcapsules. Moreover, the dose-dependent high cytotoxicity effect of the prepared microcapsules was observed on the HCT116 colorectal carcinoma cells.

Pyridinic Nitrogen Sites Dominated Coordinative Engineering of Subnanometric Pd Clusters for Efficient Alkynes' Semihydrogenation

Supported metal catalysts have played an important role in optimizing selective semihydrogenation of alkynes for fine chemicals. There into, nitrogen-doped carbons, as a type of promising support materials, have attracted extensive attentions. However, due to the general phenomenon of random doping for nitrogen species in the support, it is still atremendous challenge to finely identify which nitrogen configuration dominates the catalytic property of alkynes' semihydrogenation. Herein, it is reported that uniform mesoporous N-doped carbon spheres derived from mesoporous polypyrrole spheres are used as supports to immobilized subnanometric Pd clusters, which provide a particular platform to research the influence of nitrogen configurations on the alkynes' semihydrogenation. Comprehensive experimental results and density functional theory calculation indicate that pyridinic nitrogen configuration dominates the catalytic behavior of Pd clusters. The high contents of pyridinic nitrogen sites offer abundant coordination sites, which greatly reduces the energy barrier of the rate-determining reaction step and makes Pd clusters own high catalytic activity. The electron effect between pyridinic nitrogen sites and Pd clusters makes the reaction highly selective. Additionally, the good mesostructures also promote the fast transport of substrate. Based on the above, catalyst Pd@PPy-600 exhibits high catalytic activity (99%) and selectivity (96%) for phenylacetylene (C₈ H₆ ) semihydrogenation.

Multi-Dimensional Molecular Self-Assembly Strategy for the Construction of Two-Dimensional Mesoporous Polydiaminopyridine and Carbon Materials

Two-dimensional (2D) mesoporous polymers, combining the advantages of organic polymers, porous materials, and 2D materials, have received great attention in adsorption, catalysis, and energy storage. However, the synthesis of 2D mesoporous polymers is not only challenged by the complex 2D structure construction, but also by the low yield and difficulty in controlling the dynamics of the assembly during the generation of mesopores. Herein, a facile multi-dimensional molecular self-assembly strategy is reported for the preparation of 2D mesoporous polydiaminopyridines (MPDAPs), which features tunable pore sizes (17-35 nm) and abundant N content up to 18.0 at%. Benefitting from the abundant N sites, 2D nanostructure, and uniform-large mesopores, the 2D MPDAPs exhibit excellent catalytic performance for the Knoevenagel condensation reaction. After calcination under N₂ atmosphere, the obtained 2D N-doped mesoporous carbon (NMCs) with large and uniform pore sizes, high surface areas, abundant N content (up to 23.1%), and a high ratio of basic N species (57.0% pyridinic N and 35.9% pyrrolic N) can show an excellent CO₂ uptake density (11.7 µmol m^-2 at 273 K), higher than previously reported porous materials.

The combination of in situ photodynamic promotion and ion-interference to improve the efficacy of cancer therapy

Photodynamic therapy (PDT) is proved to be a promising modality for clinical cancer treatment. However, it also suffers from a key obstacle in association with its oxygen-dependent nature which greatly limits its effective application against hypoxic tumors. Herein, on the basis of the unique property of calcium peroxide (CaO₂), we propose an O₂-self-supply strategy for the promotion of PDT by combining the in situ O₂-generation characteristic of calcium peroxide with the photosensitive nature of porphyrin. A shell of ZIF-8 was synthesized surround the CaO₂ core to prevent the CaO₂ from premature decomposition and increased the loading of THPP efficiently. Depending on the in situ self-supply of O₂, the photosensitizer was able to exhibit an enhanced PDT effect that significantly inhibit the growth of tumor. Moreover, the enrichment of free calcium ions derived from the decomposition of CaO₂ under acidic tumor microenvironment also shows the unique ion-interference effect and contributes to the obvious inhibition against tumor growth. This work presents a synergistic strategy for the construction of a photodynamic promotion/ion-interference combined nano-platform which can also serve as an inspiration for the future design of effective nanocomposites in tumor treatment.

Chiral-Solvent-Mediated Manganese-Based Hierarchical Supraparticles with Chiroptical Activity

In this study, manganese-based multiply hierarchical chiral supraparticles (SPs), with an anisotropy factor (g-factor) of 0.102 and circular dichroism (CD) intensity of 260 mdeg at 530 nm, are successfully synthesized with polar-solvent-mediated strategies. Notably, the g-factor of the SPs is further enhanced to 0.121 by the addition of an external chiral solvent, generating a chiral biased environment, which increases their CD intensity to 320 mdeg at 500 nm. The mechanism underlying the different chirality is proposed to be a difference in the angle of tilt of ±33° between the two enantiomers of the chiral SPs, which involves a difference of ±7° between the orientation of individual nanoplatelets. Chiral solvents induce the angle between adjacent nanoplatelets to get smaller than the original structure that leads to their higher anisotropic value. These findings potentially provide a practical method for the construction of complex chiral superstructures and the regulation of chiroptical activity.

Porous organic polymers for drug delivery: hierarchical pore structures, variable morphologies, and biological properties

Porous organic polymers have received considerable attention in recent years because of their applicability as biomaterials. In particular, their hierarchical pore structures, variable morphologies, and tunable biological properties make them suitable as drug-delivery systems. In this review, the synthetic and post forming/control methods including templated methods, template-free methods, mechanical methods, electrospun methods, and 3D printing methods for controlling the hierarchical structures and morphologies of porous organic polymers are discussed, and the different methods affecting their specific surface areas, hierarchical structures, and unique morphologies are highlighted in detail. In addition, we discuss their applications in drug encapsulation and the development of stimuli (pH, heat, light, and dual-stimuli)-responsive materials, focusing on their use for targeted drug release and as therapeutic agents. Finally, we present an outlook concerning the research directions and applications of porous polymer-based drug delivery systems.

Constructing novel hyper-crosslinked conjugated polymers through molecular expansion for enhanced gas adsorption performance

The porous organic polymers have been considered as effective materials for gas storage and adsorption. Herein, we synthesized highly crystalline nitrogen-rich covalent triazine frameworks (CTFs) by polycondensation for preparing the novel hyper-cross-linked conjugated polymers (HCCPs) with tunable specific surface area and pore volume through coupling Friedel-Crafts reaction, in which 1,4-Bis(chloromethyl)benzene and 4,4-Bis(chloromethyl)biphenyl as the expansion molecules were pillared between the layers of CTF-HUST. This technology not only increased the specific surface area and total pore volume of CTF-HUST by 2.56 and 4.68 times, but also greatly enhanced the utilization of adsorption sites of CTF-HUST. The HCCP2-1.25 exhibited the highest surface area (1349.29 m²g^-1) among these HCCPs and demonstrated excellent adsorption performance for ethyl acetate (1605.14 mg/g), ethanol (1371.49 mg/g), 1,2-Dichloroethane (1971.68 mg/g), benzene (1151.77 mg/g) and toluene (1024.28 mg/g) due to the multiple C-H…O, C-H…Cl, O-H…N and C-H…π interactions between volatile organic compounds (VOCs) and HCCPs framework. Moreover, CO₂ and H₂ storage capacities of the HCCP2-1.25 were 8.02 wt% and 1.54 wt%, 1.66 and 1.67 times higher than CTF-HUST, respectively. This study developed a simple and effective molecular expansion strategy to synthesize a series of novel high-surface-area porous polymers for potential applications in the environmental field.

Nanostructured Hypercrosslinked Porous Organic Polymers: Morphological Evolution and Rapid Separation of Polar Organic Micropollutants

Nanostructured hypercrosslinked porous organic polymers have triggered immense research interest for a broad spectrum of applications ranging from catalysis to molecular separation. However, it still remains a challenge to tune their nanoscale morphology. Herein, we demonstrated a remarkable variation of morphologies of triptycene-based hypercrosslinked microporous polymers starting from irregular aggregates (FCTP) to rigid spheres (SCTP) to two-dimensional nanosheets (SKTP) from three distinct polymerization methodologies, Friedel-Crafts knitting using an external crosslinker, Scholl reaction, and solvent knitting, respectively. Further, the dramatic role of reaction temperatures, catalysts, and solvents resulting in well-defined morphologies was elucidated. Mechanistic investigations coupled with microscopic and computational studies revealed the evolution of 2D nanosheets of a highly porous solvent-knitted polymer (SKTP, 2385 m² g^-1), resulting from the sequential hierarchical self-assembly of nanospheres and nanoribbons. A structure-activity correlation of hypercrosslinked polymers and their sulfonated counterparts for the removal of toxic polar organic micropollutants from water was delineated based on the chemical functionalities, specific surface area, pore size distribution, dispersity, and nanoscale morphology. Furthermore, a sulfonated 2D sheet-like solvent-knitted polymer (SKTPS) exhibited rapid adsorption kinetics (within 30 s) for a large array of polar organic micropollutants, including plastic components, steroids, antibiotic drugs, herbicides, and pesticides with remarkable uptake capacity and excellent recyclability. The current study provides the impetus for designing morphology-controlled functionalized porous polymers for task-specific applications.

Precise fabrication of porous polymer frameworks using rigid polyisocyanides as building blocks: from structural regulation to efficient iodine capture

Porous materials have recently attracted much attention owing to their fascinating structures and broad applications. Moreover, exploring novel porous polymers affording the efficient capture of iodine is of significant interest. In contrast to the reported porous polymers fabricated with small molecular blocks, we herein report the preparation of porous polymer frameworks using rigid polyisocyanides as building blocks. First, tetrahedral four-arm star polyisocyanides with predictable molecular weight and low dispersity were synthesized; the chain-ends of the rigid polyisocyanide blocks were then crosslinked, yielding well-defined porous organic frameworks with a designed pore size and narrow distribution. Polymers of appropriate pore size were observed to efficiently capture radioactive iodine in both aqueous and vapor phases. More than 98% of iodine could be captured within 1 minute from a saturated aqueous solution (capacity of up to 3.2 g g-1), and an adsorption capacity of up to 574 wt% of iodine in vapor was measured within 4 hours. Moreover, the polymers could be recovered and recycled for iodine capture for at least six times, while maintaining high performance.

A Solvent-Polarity-Induced Interface Self-Assembly Strategy towards Mesoporous Triazine-Based Carbon Materials

Triazine-based materials with porous structure have recently received numerous attentions as a fascinating new class because of their superior potential for various applications. However, it is still a formidable challenge to obtain triazine-based materials with precise adjustable meso-scaled pore sizes and controllable pore structures by reported synthesis approaches. Herein, we develop a solvent polarity induced interface self-assembly strategy to construct mesoporous triazine-based carbon materials. In this method, we employ a mixed solvent system within a suitable range of polarity (0.223≤Lippert-Mataga parameter (Δf) ≤0.295) to induce valid self-assembly of skeleton precursor and surfactant. The as-prepared mesoporous triazine-based carbon materials possess uniform tunable pore sizes (8.2-14.0 nm), high surface areas and ultrahigh nitrogen content (up to 18 %). Owing to these intriguing advantages, the fabricated mesoporous triazine-based carbon materials as functionalized porous solid absorbents exhibit predominant CO₂ adsorption performance and exceptional selectivity for the capture of CO₂ over N₂ .

Molecular Cage-Mediated Radial Gradient Porous Sponge Nanofiber for Selective Adsorption of a Mustard Gas Simulant

Poisons and poisonous weapons in armed conflict, especially chemical warfare agents (CWAs), pose serious threats to global security. Porous materials have recently been regarded as promising candidates to defend personnel in a CWA-contaminated environment, but challenges remain for integrating these materials into protective garments without sacrificing the intrinsic flexibility of fibers. Here, we report a rigid-flexible coupling hypercross-linking methodology to create flexible sponge-like nanofibers featuring hierarchical radial gradient porous nanoarchitectures, in which the inner structure is a mesoporous multichambered network, and the outer structure is a dense domain with a microporous network structure. Experimental and computational evidence supports the contention that sponge nanofibers with distinctive pore topology and robust bendability can be designed by manipulating the flexibility of building blocks. The resulting heterogeneous nanofibers exhibit integrated properties of spatially selective superstructures, abundant micropores, interconnected mesopores, a high surface area (579 m² g^-1), remarkable flexibility, and exceptional CWA affinity, which are extraordinarily effective for adsorptive performance (498 mg g^-1). The successful synthesis of these materials might inspire the development of chemical protective materials in an efficient, self-standing, and structurally adaptive form.

Robust and Multifunctional Porous Polyetheretherketone Fiber Fabricated via a Microextrusion CO2 Foaming

Fabrication of multifunctional porous fibers with excellent mechanical properties has attracted abundant attention in the fields of personal thermal management textiles and smart wearable devices. However, the high cost and harsh preparation environment of the traditional solution-solvent phase separation method for making porous fibers aggravates the problems of resource consumption and environmental pollution. Herein, a microextrusion process that combines environmentally friendly CO₂ physical foaming with fused deposition modeling technology is proposed, via the dual features of high gas uptake and restricted cell growth, to implement the continuous production of porous polyetheretherketone (PEEK) fibers with a production efficiency of 10.5 cm s^-1 . The porous PEEK fiber exhibits excellent stretchability (234.8% strain) and good high-temperature thermal insulation property. The open-cell structure on the surface is favorable for the adsorption to achieve superhydrophobicity (154.4°) and high-efficiency photocatalytic degradation of rhodamine B (90.4%). Moreover, the parameterized controllability of the cell structure is beneficial to widening the multifunctional window. In short, the first porous PEEK physical foaming fiber, which opens up a new avenue for the application expansion, especially in the medical field, is realized.

Solvent-tailored ordered self-assembly of oligopeptide amphiphiles to create an anisotropic meso-matrix

Herein, we have developed a solvent-tailored ordered self-assembly strategy to create anisotropic nanomaterials. A trace amount of water has been found to be a predominant factor to direct peptide self-assembly into an anisotropic meso-matrix in DMSO. The obtained meso-matrix was applied to measure the anisotropic RDC parameter of organic molecules for structural elucidation.

Large-scale, robust mushroom-shaped nanochannel array membrane for ultrahigh osmotic energy conversion

The osmotic energy, a large-scale clean energy source, can be converted to electricity directly by ion-selective membranes. None of the previously reported membranes meets all the crucial demands of ultrahigh power density, excellent mechanical stability, and upscaled fabrication. Here, we demonstrate a large-scale, robust mushroom-shaped (with stem and cap) nanochannel array membrane with an ultrathin selective layer and ultrahigh pore density, generating the power density up to 22.4 W·m^-2 at a 500-fold salinity gradient, which is the highest value among those of upscaled membranes. The stem parts are a negative-charged one-dimensional (1D) nanochannel array with a density of ~10¹¹ cm^-2, deriving from a block copolymer self-assembly; while the cap parts, as the selective layer, are formed by chemically grafted single-molecule-layer hyperbranched polyethyleneimine equivalent to tens of 1D nanochannels per stem. The membrane design strategy provides a promising approach for large-scale osmotic energy conversion.

A novel self-templating strategy for facile fabrication of monodisperse polymeric microporous capsules with a tunable hollow structure

The self-templating fabrication of monodisperse polymeric microporous capsules with a tunable hollow structure for gas storage, efficient iodine capture and heterogeneous catalysis.

Hollow Carbon Sphere Nanoreactors Loaded with PdCu Nanoparticles: Void-Confinement Effects in Liquid-Phase Hydrogenations

Nanoreactors with hollow structures have attracted great interest in catalysis research due to their void-confinement effects. However, the challenge in unambiguously unraveling these confinement effects is to decouple them from other factors affecting catalysis. Here, we synthesize a pair of hollow carbon sphere (HCS) nanoreactors with presynthesized PdCu nanoparticles encapsulated inside of HCS (PdCu@HCS) and supported outside of HCS (PdCu/HCS), respectively, while keeping other structural features the same. Based on the two comparative nanoreactors, void-confinement effects in liquid-phase hydrogenation are investigated in a two-chamber reactor. It is found that hydrogenations over PdCu@HCS are shape-selective catalysis, can be accelerated (accumulation of reactants), decelerated (mass transfer limitation), and even inhibited (molecular-sieving effect); conversion of the intermediate in the void space can be further promoted. Using this principle, a specific imine is selectively produced. This work provides a proof of concept for fundamental catalytic action of the hollow nanoreactors.

Polyoxometalates encapsulated into hollow double-shelled nanospheres as amphiphilic nanoreactors for an effective oxidative desulfurization

Although some catalytic hollow nanoreactors have been fabricated in the past, the encapsulated active species focus on metal nanoparticles, and a method for polyoxometalate (POM)-containing hollow nanoreactors has seldom been developed. Herein, we report a synthetic strategy towards POM-based amphiphilic nanoreactors, where the hollow mesoporous double-shelled SiO₂@C nanospheres were used to encapsulate Keggin-type H₃PMo₁₂O₄₀ (PMo₁₂). The outer hydrophobic carbon shell was beneficial for the enrichment of the organic substrate around the nanoreactor and simultaneously prevented the deposition of POMs on the outer surface of the nanoreactor. The inner hydrophilic silica cavity was modified by two types of organosilanes, which not only created an amphiphilic cavity environment but also acted as an anchor to mobilize PMo₁₂. As the POM nanoreactor had the hydrophilic@hydrophobic SiO₂@C shell and an amphiphilic cavity, both dibenzothiophene (DBT) and H₂O₂ could smoothly diffuse into the nanosized cavity, where the DBT was effectively oxidized (conversion: >99%) by the immobilized PMo₁₂ under mild conditions. Importantly, the control experiments indicated that the confined effect of nanoreactor, amphiphilic SiO₂@C double-shell, unique cavity environment, and mesoporous channels accounted for an excellent catalytic performance. Moreover, the nanoreactor was robust and could be reused for five cycles without loss of activity.

Self-assembly of block copolymers towards mesoporous materials for energy storage and conversion systems

This paper reviews the progress in the field of block copolymer-templated mesoporous materials, including synthetic methods, morphological and pore size control and their potential applications in energy storage and conversion devices.

Branched macromonomers from catalytic chain transfer polymerisation (CCTP) as precursors for emulsion-templated porous polymers

Catalytic chain transfer polymerisation (CCTP) is combined for the first time with emulsion-templating to generate polyHIPE materials where functionality and rigidity can be tightly tailored, broadening their scope of application.

Facile synthesis of a linear porous organic polymer via Schiff-base chemistry for propyne/propylene separation

Synthesis of the linear porous organic polymer (L-POP) for selective separation of acetylene (C₃H₄) from ethylene (C₃H₆).

Novel amino-functionalized hypercrosslinked polymer nanoparticles constructed from commercial macromolecule polystyrene via a two-step strategy for CO2 adsorption

Commercial polymers have large cost advantage to drive HCPs to industrialize. The AHCPNPs using commercial PS as main block prove that it still has well-defined microporous structure, high specific surface area and extremely CO₂ capture capacity.

Core hyper-cross-linked star polymers from block polymer micelle precursors

Hyper-cross-linking of a core of block polymer micelles produces core cross-linked polymer with a spacious hyper-cross-linked core, which is solution-processible.

A Versatile Solvent-Induced Polymerization Strategy To Synthesize Free-Standing Porous Polymer Nanosheets and Nanotubes for Fast Iodine Capture

Two-dimensional (2D) porous polymers have demonstrated great potential in gas capture and surface catalysis as well as energy storage and conversion. Current synthesis of 2D porous polymers strongly depends on the usage of templates or an additional exfoliation process. The resultant products have uncontrollable morphology and structure, low structure integrity, and relatively low yield. Herein, a facile and high-throughput solvent-induced polymerization strategy to prepare ultrathin free-standing 2D porous hyper-cross-linked polymer nanosheets with large surface area and high sulfur content by cross-linking steric hexakis(benzylthio)benzene and thiophene is reported. Using this approach, the morphologies (nanosheets and nanotubes) and specific surface areas (658-1150 m² g^-1) of porous hyper-cross-linked polymers can be simply tailored by adjusting the cross-linking degree between monomers. The as-synthesized porous hyper-cross-linked polymer nanotubes exhibit promising iodine capture performance, including a superior iodine uptake capacity (∼270 wt %) and a rapid equilibrium adsorption (within 60 min). This method will pave a new avenue for the synthesis of advanced 2D porous polymers for various applications.

Guided Assembly of Well-Defined Hierarchical Nanoporous Polymers by Lewis Acid-Base Interactions

Three-dimensional hierarchical nanoporous polymers and carbon nanomaterials with well-defined superstructures are of great interest for various intelligent applications, whereas a facile and versatile approach to access those materials with a high surface area, stable well-defined morphology, and ordered pores still remains a significant challenge. Herein, we report a self-regulated Lewis acid-base interaction-mediated assembly strategy for the in situ synthesis of morphology-engineered hyper-cross-linked porous polymers and carbon materials. A series of functionalized aromatic compounds (FAC) is subjected to self-cross-linking via classic Friedel-Crafts chemistry to achieve stable porous polymers with a high surface area. Varying the monomer/catalyst combination had a dramatic effect on the acid-base interaction, facilitating the tailoring of the self-assembled morphologies from nanotubes to hollow nanospheres, and even nanosheets. A mechanistic study showed that the byproducts generated during cross-linking orchestrate the interactions between the catalyst (acid) and FAC (base) and simultaneously drive the self-assembly to yield specific morphologies. Based on the rigid hollow polymer framework and intrinsic hydroxyl functionality, the hyper-cross-linked hollow nanospheres were easily transformed to an acid-functionalized catalyst for efficient biodiesel production. Moreover, high-quality porous carbonaceous nanocounterparts such as carbon nanotubes, hollow carbon nanospheres, and carbon nanosheets could also be produced by direct pyrolysis of the corresponding polymer precursors. These findings may provide guidance for the facile design of morphology-controlled functionalized polymers and carbon nanomaterials for various applications.

Dispersible microporous diblock copolymer nanoparticles via polymerisation-induced self-assembly

Dispersible microporous polymer nanoparticles formed via the RAFT-PISA polymerisation of divinylbenzene and fumaronitrile using a PEG macro-CTA.