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Various conventional reactions in polymer chemistry have been translated to the supramolecular domain, yet it has remained challenging to devise living supramolecular polymerization. To achieve this, self-organization occurring far from thermodynamic equilibrium—ubiquitously observed in nature—must take place. Prion infection is one example that can be observed in biological systems. Here, we present an ‘artificial infection’ process in which porphyrin-based monomers assemble into nanoparticles, and are then converted into nanofibres in the presence of an aliquot of the nanofibre, which acts as a ‘pathogen’. We have investigated the assembly phenomenon using isodesmic and cooperative models and found that it occurs through a delicate interplay of these two aggregation pathways. Using this understanding of the mechanism taking place, we have designed a living supramolecular polymerization of the porphyrin-based monomers. Despite the fact that the polymerization is non-covalent, the reaction kinetics are analogous to that of conventional chain growth polymerization, and the supramolecular polymers were synthesized with controlled length and narrow polydispersity. Self-organization that occurs far from thermodynamic equilibrium is ubiquitous in nature but has remained challenging to control in synthetic supramolecular systems. A complex system has now been devised that displays such behaviour. Porphyrin derivative monomers undergo living supramolecular polymerization, a reaction underpinned by the interplay of two supramolecular polymerization pathways.

Chemical, petrochemical, energy, and environment-related industries strongly require high-performance nanofiltration membranes applicable to organic solvents. To achieve high solvent permeability, filtration membranes must be as thin as possible, while retaining mechanical strength and solvent resistance. Here, we report on the preparation of ultrathin free-standing amorphous carbon membranes with Young's moduli of 90 to 170 gigapascals. The membranes can separate organic dyes at a rate three orders of magnitude greater than that of commercially available membranes. Permeation experiments revealed that the hard carbon layer has hydrophobic pores of ~1 nanometer, which allow the ultrafast viscous permeation of organic solvents through the membrane.

Machine learning is emerging as a powerful tool for the discovery of novel high-performance functional materials. However, experimental datasets in the polymer-science field are typically limited and they are expensive to build. Their size (< 100 samples) limits the development of chemical intuition from experimentalists, as it constrains the use of machine-learning algorithms for extracting relevant information. We tackle this issue to predict and optimize adhesive materials by combining laboratory experimental design, an active learning pipeline and Bayesian optimization. We start from an initial dataset of 32 adhesive samples that were prepared from various molecular-weight bisphenol A-based epoxy resins and polyetheramine curing agents, mixing ratios and curing temperatures, and our data-driven method allows us to propose an optimal preparation of an adhesive material with a very high adhesive joint strength measured at 35.8 ± 1.1 MPa after three active learning cycles (five proposed preparations per cycle). A Gradient boosting machine learning model was used for the successive prediction of the adhesive joint strength in the active learning pipeline, and the model achieved a respectable accuracy with a coefficient of determination, root mean square error and mean absolute error of 0.85, 4.0 MPa and 3.0 MPa, respectively. This study demonstrates the important impact of active learning to accelerate the design and development of tailored highly functional materials from very small datasets.

There are increasing requirements worldwide for advanced separation materials with applications in environmental protection processes. Various mesoporous polymeric materials have been developed and they are considered as potential candidates. It is still challenging, however, to develop economically viable and durable separation materials from low-cost, mass-produced materials. Here we report the fabrication of a nanofibrous network structure from common polymers, based on a microphase separation technique from frozen polymer solutions. The resulting polymer nanofibre networks exhibit large free surface areas, exceeding 300 m 2  g −1 , as well as small pore radii as low as 1.9 nm. These mesoporous polymer materials are able to rapidly adsorb and desorb a large amount of carbon dioxide and are also capable of condensing organic vapours. Furthermore, the nanofibres made of engineering plastics with high glass transition temperatures over 200 °C exhibit surprisingly high, temperature-dependent adsorption of organic solvents from aqueous solution. Mesoporous polymeric materials are good candidates for advanced separation materials, though their low-cost production remains challenging. Here, the authors report a microphase separation technique for the fabrication of nanoporous networks from frozen solutions of common polymers.

Polymeric impurities in liquid crystals are known to perturb liquid-crystalline order. It is now shown that spatial gradients in the order, created by illuminating the materials with ultraviolet light, can be used to generate forces that allow the polymers to be concentrated or dispersed in the liquid crystal. Collective long-range interactions between micrometre-sized impurities in liquid crystals result from the elastic distortion of the liquid-crystalline order 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 . For substantially smaller polymeric impurities, what is relevant is not the elastic interaction between them but the coupling between the scalar nematic order parameter S and the polymer concentration φ . This coupling originates from local molecular interactions, but becomes long ranged because the total polymer concentration is conserved over the whole sample. Here, we propose a new mechanism by which the spatial variation of S generates a force, mediated by the coupling between S and φ , that transports nanoscale polymeric impurities. We have designed a prototype of a molecular manipulator that moves molecules along spatial variations of the scalar order parameter, modulated in a controlled manner by spot illumination of an azobenzene-doped nematic phase with ultra-violet light. We also demonstrate the use of the manipulator for the measurement of the anisotropic diffusion constant of a polymer in the nematic phase. The manipulator can control the spatial variation of the polymer concentration, thus showing promise for use in the design of hybrid soft materials.

Adsorptive-photocatalytic electrospun nanofiber membranes have received remarkable attention as they could provide an excellent solution for the effective treatment of wastewater. However, the mechanical properties of nanofiber have limited their use in pressure-driven filtration applications. In this study, dual-layered MoS2/PAN-CA adsorptive-photocatalytic-based membranes have been successfully fabricated using molybdenum disulphide/polyacrylonitrile (MoS2/PAN) nanofiber coated porous cellulose acetate (CA) membranes. The fabricated CA membranes were coated with electrospun MoS2/PAN nanofiber via the electrospinning technique. Subsequently, hot-pressed treatment was applied to the fabricated membrane to form a stronger attachment between the CA and MoS2/PAN nanofiber layers. The physicochemical properties of the fabricated membranes were characterised using scanning electron microscopy (SEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analyzer (TGA), water contact angle (WAC), porosity analysis, and tensile strength test. In addition, the membrane separation performance of the fabricated nanofiber membranes was evaluated in terms of water flux and contaminant rejection using a self-assembled cross-flow filtration system. The MoS2/PAN-CA membrane demonstrated improved physicochemical and structural properties where WAC, porosity and mechanical strength increased up to 38% (44.0°), 25% (55%) and 26% (32.1 MPa), respectively, as compared to pristine CA membrane. Upon hot-pressed treatment at a temperature of 120 °C, pure water flux of MoS2/PAN-CA membrane improved by 28% to 36.3 Lm−2 h−1. These improved properties of dual-layered adsorptive-photocatalytic MoS2/PAN-CA membranes recommend it as a potential membrane material to treat various pollutants in water and wastewater.

The present work focused on the determination of texture, morphology, crystallinity, and gas adsorption characteristics of porous graphene prepared from rice husks ashes at different stabilization temperature. The stabilization temperature applied in this work is 100 °C, 200 °C, 300 °C, and 400 °C to convert rice husk into rice husk ashes (RHA). Chemical activation was adopted at temperature 800 °C using potassium hydroxide (KOH) as dehydrating agent at (1:5) impregnation ratio to convert RHA into rice husk ashes-derived graphene (GRHA). The resultant GRHA were characterized in terms of their morphological changes, SSA, crystallinity, and functional group with TEM, the BET method, Raman spectroscopy, and XRD analysis, respectively. Results from this study showed that the SSA of the GRHA at stabilization temperature 200 °C (1556.3 m 2 /g) is the highest compared to the other stabilization temperature. Raman spectroscopy analysis revealed that all GRHA samples possess D, G, and 2D bands, which confirm the successful synthesis of the rice husks into porous graphene-like materials, known as GRHA. Appearance of diffraction peak in XRD at 44.7° indicating the graphitic structure of all the GRHA samples. Meanwhile, the TEM images of GRHA200 exhibited wrinkled structures due to the intercalation of oxygen and a few layers of graphene flakes. These wrinkled structures and graphene layers are the other factors that lead to the highest SSA of GRHA200 compared to other prepared samples GRHA. Furthermore, the adsorption capacity of CH 4 for GRHA200 is up to 43 cm 3 /g at 35 bar and ambient temperature, almost double the adsorption capacity performance of GRHA400 at the same operating pressure and temperature.

Environmental crisis and water contamination have led to worldwide exploration for advanced technologies for wastewater treatment, and one of them is photocatalytic degradation. A one-dimensional hollow nanofiber with enhanced photocatalytic properties is considered a promising material to be applied in the field. Therefore, we synthesized titanium dioxide hollow nanofibers (THNF) with extended surface area, light-harvesting properties and an anatase–rutile heterojunction via a template synthesis method and followed by a calcination process. The effect of calcination temperature on the formation and properties of THNF were determined and the possible mechanism of THNF formation was proposed. THNF nanofibers produced at 600 °C consisted of a mixture of 24.2% anatase and 75.8% rutile, with a specific surface area of 81.2776 m2/g. The hollow nanofibers also outperformed the other catalysts in terms of photocatalytic degradation of MB dye, at 85.5%. The optimum catalyst loading, dye concentration, pH, and H2O2 concentration were determined at 0.75 g/L, 10 ppm, pH 11, and 10 mM, respectively. The highest degradation of methylene blue dye achieved was 95.2% after 4 h of UV irradiation.

Measuring flow of gases is of fundamental importance yet is typically done with complex equipment. There is, therefore, a longstanding need for a simple and inexpensive means of flow measurement. Here, gas flow is measured using an extremely simple device that consists of an Ar plasma‐treated polydimethylsiloxane (PDMS) slab adhered on a glass substrate with a tight seal. This device does not even have a channel, instead, gas can flow between the PDMS and the glass by deforming the PDMS wall, in other words, by making an interstice as a temporary path for the flow. The formation of the temporary path results in a compressive bending stress at the inner wall of the path, which leads to the formation of well‐ordered wrinkles, and hence, the emergence of structural color that changes the optical transmittance of the device. Although it is very simple, this setup works sufficiently well to measure arbitrary gases and analyzes their flow rates, densities, and viscosities based on the change in color. It is also demonstrated that this technique is applicable to the flow‐induced display of a pattern such as a logo for advanced applications. It is demonstrated that a super simple device consisting of a glass and a plasma‐treated polydimethylsiloxane (PDMS) is useful for measuring gases based on the change in color caused by flow‐induced deformation of the PDMS. This technique allows to analyze flow rate, density, and viscosity of the gases, as well as, to display an arbitrary pattern such as a logo.

Oxynitride glasses in Si-Al-O-N system were synthesized to investigate atomic arrangements in those glasses. Aerogels of silica (SiO 2 ) and silica-alumina (SiO 2 -Al 2 O 3 ) system were fabricated by drying wet gels in supercritical CO 2 condition. The SiO 2 gels were prepared from the silicon alkoxide with CH 3 groups and the SiO 2 -Al 2 O 3 gels were prepared from silicone and aluminum alkoxides. Ammonolysis were performed at T N  = 750–1400 °C to synthesize oxynitride glasses. The nitrogen concentration in the resultant glasses increased with the increase in the ammonolysis temperatures and exceeded 34 eq.% by ammonolysis at 1300 °C. The specific surface area of these aerogels has been 1941 and 1159 m 2  g −1 , respectively. The glass structures were investigated by adopting 29 Si and 27 Al NMR measurements. In silicon oxynitride glasses, it was revealed that only one N atom occupies the nearest neighbor site around Si after ammonolysis at T N  < 1200 °C, while two or more N atoms occupy the nearest neighbor site around Si after ammonolysis at T N  > 1300 °C. In Si-Al-O-N glasses, the number of N atoms at around neighboring to Si atom varied with ammonolysis temperature but any traces of Al-N bonds were not found, indicating the bridging N in the form of Si-N-Al was absent in the glasses. Nitrogen contents of oxynitride glasses prepared from silica-based aerogels with CH 3 groups (ON-CH 3 ) and those doped with Al and Eu ions (ON-AE) increased with increase of ammonolysis temperature. The 29 Si NMR spectra differed between ON-CH 3 and ON-AE. Highlights Silicon-based oxynitride glasses were prepared from aerogels via ammonolysis at high temperature. Nitrogen contents of the oxynitride glasses reached to higher than 34 eq.%. The local structures of the oxynitride glasses were investigated by 29 Si and 27 Al NMR measurements. It was found that most of inserted nitrogen was bonded to Si atoms.