The synthesis of supported multielement transition metal phosphides (TMPs) to exploit the synergistic interplay between electronic and geometric effects resulting from the presence of different metals in the material and the arrangement of heterogeneous atoms is pivotal for reducing metal content while offering multiple active sites. However, the integration of Ni, Co, and P, for example, into a nanostructured carbon network to develop self‐supporting NixCoyP bimetallic phosphides is limited by several factors, including the synthesis and the discrepancy between the crystal structure of the respective monometallic phosphides. Moreover, conventional synthesis of supported TMPs often separates nanoparticles, support and phosphidation steps, which do not allow tailoring of physical and catalytic properties via particle support, electronic and geometric interactions. Herein, an innovative solid‐state, ex situ phosphidation‐free approach tailored to synthesize a library of self‐supporting NixCoyP TMPs in N,S,P‐modified nanostructured carbon networks generated together with NixCoyP particles is presented. Extensive multivariate characterization validates the unique properties of NixCoyP bimetallic materials with enhanced electrocatalytic performance for the hydrogen evolution reaction and the selective electroconversion of biomass‐derived 5‐hydroxymethylfurfural (5‐HMF) to value‐added 2,5‐furandicarboxylic acid (FDCA) with 90–100% Faradaic efficiency. Overall, the synthesis expands the possibilities for tailoring the microstructure of supported TMPs for improved physical/catalytic properties.

The creation of nanostructured materials with a triply periodic minimal surface (TPMS), defined as a zero mean curvature surface having periodicity in three-dimensional space, is an emerging solution to optimize transport (i.e., the ion-conductivity and hydraulic permeability) through the next-generation of electrolyte and ultrafiltration (UF) membranes. Here, we used an amphiphilic ABC-type block copolymer (BCP) (namely, polystyrene-block-poly(2-vinylpyridine)-block-poly(ethylene oxide) (PS-b-P2VP-b-PEO)) to generate symmetric thick films (~8 μm) composed entirely of a TPMS-based structure, consisting of a PS matrix with a double gyroid (DG) minimal surface and hydrophilic stimuli-responsive (P2VP/PEO) nanochannels. To produce the core/shell DG-structured monoliths, we used a process combining the nonsolvent-induced phase separation (NIPS) process with a solvent vapor annealing (SVA) treatment. From such symmetric ABC-type BCP-thick films generated by NIPS-SVA, a mean hydraulic permeability as high as 514 L h-1 m-2 bar-1 was measured. This mean value was revealed to be nearly equal to that of asymmetric PS-b-P2VP-b-PEO membranes manufactured by NIPS, which have a substructure with an implicit irregular and random distribution of the internal pore structure and a skin layer with P2VP/PEO nanopores arranged into a hexagonal array.

Cellulose-based materials are a sustainable alternative to polymers derived from petroleum. Cellulose nanocrystal (CNC) is a biopolymer belonging to this family; it is commonly known for its important physical and chemical properties and ability to form a film. Modifying CNC via electrostatic interaction provided by cationic polymers is a facile and promising technique to enlarge the application of CNC. Herein, we report the preparation of films, from blends of negatively charged CNC and positively charged poly (trimethyl aminoethyl methacrylate) (PTMAEMA). The interaction between CNC and PTMAEMA was verified by using a quartz crystal microbalance with dissipation monitoring (QCM-D), as well as by measuring the particle size and ζ-potential of the casting mixture. To favor the application of the nanocomposite film in water treatment, the film was supported on Whatman™ paper, and adsorption tests were conducted using perfluorooctanoic acid (PFOA) as a model compound for the family of persistent fluorinated pollutants known as PFAS (per- and polyfluoroalkyl substances).

Flow-through reactors made of highly porous hierarchical micro/meso/macroporous carbon monoliths (CM) were developed to decontaminate water containing pharmaceutical micropollutants (antibiotics). CM were prepared from hierarchical meso/macroporous silica monoliths as sacrificial templates after impregnation with sucrose as a carbon precursor, hydrothermal carbonization, and subsequent pyrolysis and dissolution of silica by NaOH. CM were fully characterized by nitrogen sorption at 77 K, Hg porosimetry, scanning electron microscopy, transmission electron microscopy, microtomography, permeability measurements, X-ray photoelectron spectroscopy, and chemical analysis. CM exhibit a large surface area (1058 m(2) g(-1)), a large pore volume (6.5 mL g(-1)), high permeability, a homogeneous interconnected macropore network (22 mu m), bimodal mesopores (6 and 15 nm), micropores (0.85 nm), and a large number of C=O and COO- groups. They are basic in water (pH 9) and negatively charged. First, adsorption of a single pharmaceutical molecule, tetracycline (TC), was studied. Isotherms of adsorption, kinetics, and diffusion were used to study the mechanism of adsorption on CM, and the process was found to be governed by electrostatic interactions. Then, a mixture of several antibiotics (ciprofloxacin, amoxicillin, sulfamethoxazole, and TC, 20 mg L-1 each) was used. The sorption capacity for antibiotics peaked at 815 mg g(-1). In a recirculation flow configuration, with a flow rate of 1 mL min(-1), CM could remove 93% of the antibiotics. These CM could represent a highly efficient solution for the purification of real wastewater containing pharmaceutical molecules, which are generally found at much lower concentrations (from a few nanograms per liter to micrograms per liter). Regeneration of CM was successfully achieved by washing with HCl (0.1 M).

Amphiphilic block copolymer (BCP) thick films with stimuli-responsive pores are promising candidates for the manufacturing of next-generation ultrafiltration (UF) membranes since their smart nanochannels facilitates the removal of fouling which is considered as one of the biggest challenges in membrane technology. In this work, a well-defined polystyrene-block-poly(2-vinylpyridine)-block-poly(N-isopropylacrylamide) (PS-b-P2VP-b-PNIPAM) terpolymer was prepared for the first time via reversible addition-fragmentation chain transfer polymerization. The combination of the nonsolvent-induced phase separation process with a solvent vapor annealing treatment was used to produce nanostructured pH- and thermo-double sensitive ABC-type BCP thick films. Here, the NIPS-made PS-b-P2VP-b-PNIPAM thick film, comprising a microporous spinodal-type network substructure, topped by a dense thin layer of poorly defined nanopores is transformed into a monolith entirely composed of a well-ordered perforated lamellar (PL) phase upon exposure to a chloroform vapor during 6 h. Such kind of PL-structured monoliths, showing a permeance value as high as 18 L h(-1) m(-2) bar(-1) at 46 degrees C and pH = 7 with an excellent temperature cyclability, are highly desired to manufacture smart separation-based UF materials able to transit their pore state from hydrophilic to hydrophobic (and vice versa), thereby leading to much more efficient detachment of foulants during the cleaning process.

Vertically oriented nanoporous cylinders, demonstrating an unprecedented alignment persistence, were produced within freestanding poly(1,1-dimethyl silacyclobutane)-block-polystyrene-block-poly(2-vinyl pyridine) (PDMSB-b-PS-b-P2VP) layers (similar to 15 mu m thick) blended with short PS-b-P2VP chains by combining the non-solvent induced phase separation (NIPS) process with a solvent vapor annealing (SVA) treatment. Here, the NIPS step allowed for the formation of an asymmetric and porous PDMSB-b-PS-b-P2VP film having a top surface exhibiting poorly-defined nanopores while the subsequent SVA treatment enabled to produce a symmetric layer that possesses highly-ordered cylindrical nanodomains arranged into a 27 nm period square array. As the unblended NIPS/SVA-made PDMSB-b-PS-b-P2VP monoliths exhibited a mixed orientation of parallel and perpendicular cylinders, a blending strategy was used to achieve tetragonally-packed PDMSB and P2VP nanodomains having an exceptional vertical alignment persistence. Such solvent-annealed (3 h, CHCl3) PDMSB-b-PS-b-P2VP monoliths blended with 20 wt% of PS-b-P2VP chains showed a water permeance close to the value measured through their parent NIPS-made terpolymer films having poorly-ordered nanopores.

Metal Organic Frameworks (MOFs) present high surface areas, various pore topology as well as good stabilities. The functionalities and porosity can be tuned by using different linkers with various functional groups and a wide range of linker lengths. These properties make them good candidates in membrane separation applications. In this work, we propose a simple UiO-66 MOF-based membrane fabrication method following two steps. First, the α-alumina tubular membrane support was dip-coated with MOF-polymer hybrid nanoparticles (NPs). These NPs were prepared via one-pot synthesis by adding poly (methacrylic acid)-b-poly (methyl methacrylate) (PMAA-b-PMMA) NPs to the classical acetic acid-modulated UiO-66 or UiO-66-NH2 synthesis formulation. Second, secondary membrane growth was applied to give rise to a continuous and homogeneous crystalline MOF membrane layer. The gas permeances (He, N2, CO2 and SF6) tests confirmed high membrane permeability with no macro-defects. The as-prepared membranes that were used for dye separation (Rhodamine B) showed relatively good separation capacity.

Mesoporous ZSM‐5 catalysts were prepared from a commercial ZSM‐5 (Si/Al=15), using a 2‐step micelle‐templating procedure. By varying the NaOH/Si synthesis ratio in the range of 0.3‐0.7, ZSM‐5 catalysts with different textural and acidic properties were obtained. Increasing the NaOH/Si ratio in the synthesis gel leads to zeolites that feature reduced number of Brønsted acid sites, but higher mesopore volume, which allows for reducing the diffusion path length. In order to assess the best compromise between Brønsted acidity and mesopore volume two test reactions were run. The alkylation of phenol with tert‐butyl alcohol allowed to evidence the accessibility of bulky molecules to active sites. The esterification of benzyl alcohol with hexanoic acid allowed to probe the specificity of Brønsted acid sites in ZSM‐5. The best compromise was found for micro‐/mesoporous ZSM‐5 catalysts prepared with the ratio 0.38

Colloidaly stable carboxylate-based metal organic frameworks (MOFs), grown from acid decorated nanoparticles synthesized via PISA.

With the growing environmental concerns that society is nowadays facing, the development of biobased materials has intensified and biobased polyisocyanates have emerged in the market. Their commercializa-tion enabled to synthesize the first four biobased polyurethanes foams (PUFs) from biobased isocyanates, containing up to 93% of renewable carbons. Their mechanical and thermomechanical properties were compared. In particular, one of the four PUF formulations was very promising: it foamed at room temperature and produced a low density foam 78 kg/m(3), comparable to that of conventional fossil-based PUFs. To consider the full life cycle of such materials, these PUFs were upcycled and reshaped to bulk polyurethanes (PUs) by transcarbamoylation reaction up to 5 cycles. Moreover, a unique material (mixPU) composed of the four PUFs was prepared and reshaped, by compression molding at 160 degrees C for 30 min, thus demonstrating the potential of this recycling pathway for PUFs from different origins. Finally, stress-relaxation experiments were carried out to evaluate the dynamic properties of the mixPU material, which was shown to behave as a covalent adaptable network.

A versatile approach has been developed to prepare small mesoporous silica particles with simultaneous control of the internal ordered pore structure and the external particle surface. Mixed polyion complex (PIC) micelles are used as silica structure-directing agents: they result from the complexation of a polybase with two polyacid double-hydrophilic block copolymers (DHBC) having either a poly(ethylene oxide) (PEO) based-block or a polyacrylamide (PAM) block. The ionizable block in both DHBC is poly(acrylic acid), which complexes oligochitosan to form the core of the electrostatic complex. By varying the architecture of the PEO-based block (linear or comb-shaped) and the synthesis parameters, it is possible to modulate the pore structure from 3D cage like to 2D-hexagonal and lamellar mesostructures. Replacing a fraction of the PEO-based polymers with DHBC having a polyacrylamide block that has no affinity for silica is shown to affect silica-micelle interactions and material growth. While the PEO chains interact with silica to form the hybrid interface, the PAM chains act as capping agents and control the external surface of the particles. Increasing the relative amount of PAM-based DHBC leads to the formation of small discrete mesoporous silica particles that are reduced in size to 200 nm. The particle size reduction and particle surface stabilization by PAM chains can be explained by considering not only the existence of a mixed corona of PAM and PEO in PIC micelles but also the differentiated solubility of these two neutral blocks induced by silica condensation. Thus, the present strategy allows independent decrease of the particle size and tuning of its pore structure.

UiO-MOFs are based on zirconium cluster and carboxylic acid linkers. They have excellent chemical and thermal stability, tolerance to linkers of different length and functionalities, making them good candidates for a broad range of applications. However, difficulties of processing the polycrystalline powder of MOFs limit their application. Here, we report for the first time the synthesis of the UiO-66 in the presence of a well-defined poly (methacrylic acid)-b-poly (methyl methacrylate) (PMAA-b-PMMA) nanoparticles (NPs) prepared via Reversible Addition-Fragmentation Chain-transfer Polymerization controlled Polymerization Induced Self-Assembly (RAFT-PISA). The PMAA-b-PMMA NPs with multi carboxylic acid groups on their surface, well defined in shape and size, act as multivalent connecting agent for the synthesis of the UiO-66. The resulting colloidally stable UiO-polymer NPs are crystalline, porous, and with an improved processability as was demonstrated by the preparation of a thin film nanocomposite (TFN) membrane. This membrane was applied in the filtration of Nickel (II) phthalocyanine-tetrasulfonic acid tetrasodium salt aqueous solution obtaining a water permeability circa 20 L m- 2 h-1 bar-1 with a rejection of more than 90%. This unprecedented facile synthesis approach could be universally applied to other MOFs, expanding their application in different fields due to their enhanced processability.

The highest total organic carbon (TOC) and color removal efficiency of Acid Orange 7 (0.1 mM initial concentration) on graphite carbon/carbon nanotubes electrodes (KS44/CNT) reached more than 98% in three hours of Electro-Fenton (EF) treatment under optimal conditions (pH=3 and I=20 mA), compared to carbon graphite electrode developed without carbon nanotubes (KS44-0). The apparent kinetic constants of degradation were 0.17 and 0.12 min−1 for the KS44-(20)/CNT and KS44-0, respectively. The long-term stability and system durability were attributed to the graphite carbon/CNT electrodes due to continuous operating treatment that allowed processing efficiency and reusability without any decrease of the catalytic activity in time after five cycles of use. Regardless of the medium, superior decolorization and TOC removal efficiency were obtained for electrodes (KS44-(20)/CNT) containing 20 wt% of ferrocene powder as catalyst for CNTs’ growth and iron nanoparticle establishment. Furthermore, the presence of CNTs and iron particles as precursors enhanced drastically the electrochemical and physical properties of the electrode synthesized in a one-step process. The results confirmed that carbon electrodes behave as multifunctional materials acting both as adsorbent and active cathode in the electro-Fenton process for the destruction and total mineralization of Acid Orange 7 (AO7) as a model for organic contaminated wastewater.

Calcined silica SiO2 hollow spheres (SHS), with a specific surface area of 523 m2 g−1, were used as porous scaffolds of ammonia borane (AB). AB is used as precursor of boron nitride BN. By capillary effect, AB was infiltrated into the porosity of the SHS, and the as-obtained composite AB@SHS was pyrolyzed. Up to 160 °C, AB transforms into polyborazylene (PB); as a result, the composite PB@SHS was produced. Up to 600 °C, BN forms, and the composite BN@SHS was produced. Both composites are porous, with a specific surface area of 360 and 296 m2 g−1 respectively. Results from MAS NMR and XPS analyses showed that PB@SHS and BN@SHS contain B–O bonds, with more B–O bonds and possibly Si–O–B bonds for the latter. In other words, PB@SHS is made of PB, B–O bonds, and SiO2, while BN@SHS is made of BN, B–O bonds, possibly a Si–O–B interface, and SiO2. Based on first attempts, BN@SHS appeared to have a potential for improving the CO2 adsorption properties of the calcined SHS. Expressed in cm3(CO2) g−1, the CO2 uptakes are 6.7 for BN@SHS and 6.3 for the calcined SHS, at 30 °C under 1.5 bar CO2; but expressed in mm3(CO2) m−2, the respective CO2 uptakes are 22.6 and 12.

This paper discusses the preparation of an asymmetric microfiltration carbon membrane made of mineral coal powder and phenolic resin. Tubular supports were obtained via extrusion of a paste prepared by mixing a carbon powder, a solution of phenolic resin and organic additives. The green tubes were cured then carbonized at 700 °C under nitrogen flow. Porous supports with an average pore diameter of 9 μm and 38% porous volume were achieved. The material presents high chemical and mechanical resistances. Experimental data showed that the particle size and homogeneity of the carbon powder are directly responsible of the average pore size and distribution of the final material. Phenolic resin acts as binder, carbon precursor and porosity agent with a constant 25% contribution to the total porous volume. The microfiltration layer was coated by means of the slip casting process, using a suspension of finely ground carbon powder dispersed in a phenolic resin alcoholic solution. Carbonization at 700 °C was necessary to obtain a defect-free layer with an average pore diameter of 0.5 and 25 μm thickness. The membrane material displayed a hydrophobic character. To increase its hydrophilic character, the membrane was oxidized under air at 350 °C for 30 min then tested for industrial wastewater filtration. The membrane’s behavior complied with the Darcy’s law even after oxidation. Nevertheless, the oxidation step changed the hydrophobic character of the membrane to a hydrophilic one. In fact, this treatment had a direct impact on the permeability of the membrane and on the filtration flux of industrial wastewater. The latter increased by a factor of 2.5 to 5. In addition, a total retention in turbidity was achieved with 47% of the organic matter retained by the membrane. Due to a complexation between the organic elements Ca2+ and Mg2+, the retention of these divalent ions was also important.

Additive manufacturing of Polymer-Derived Ceramics (PDCs) is regarded as a disruptive fabrication process that includes several technologies such as light curing and ink writing. However, 3D printing based on material extrusion is still not fully explored. Here, an indirect 3D printing approach combining Fused Deposition Modeling (FDM) and replica process is demonstrated as a simple and low-cost approach to deliver complex near-net-shaped cellular Si-based non-oxide ceramic architectures while preserving the structure. 3D-Printed honeycomb polylactic acid (PLA) lattices were dip-coated with two preceramic polymers (polyvinylsilazane and allylhydridopolycarbosilane) and then converted by pyrolysis respectively into SiCN and SiC ceramics. All the steps of the process (printing resolution and surface finishing, cross-linking, dip-coating, drying and pyrolysis) were optimized and controlled. Despite some internal and surface defects observed by topography, 3D-printed materials exhibited a retention of the highly porous honeycomb shape after pyrolysis. Weight loss, volume shrinkage, roughness and microstructural evolution with high annealing temperatures are discussed. Our results show that the sacrificial mold-assisted 3D printing is a suitable rapid approach for producing customizable lightweight highly stable Si-based 3D non-oxide ceramics.

The design of hydrophobic surfaces requires a material which has a low solid surface tension and a simple fabrication process for anchoring and controlling the surface morphology. A generic method for the spontaneous formation of robust instability patterns is proposed through the hydrosilylation of a fluoroalkene bearing dangling chains, Rf = C6F13(CH2)3-, with a soft polymethylhydrosiloxane (PMHS) spin-coated gel polymer (0.8 μm thick) using Karstedt catalyst. These patterns were easily formed by an irreversible swelling reaction due to the attachment of a layer to various substrates. The buckling instability was created by two different approaches for a gel layer bound to a rigid silicon wafer substrate (A) and to a soft nonswelling silicone elastomer foundation (B). The observations of grafted Rf-PMHS films in the swollen state by microscopy revealed two distinct permanent patterns on various substrates: dotlike of wavelength λ = 0.4-0.7 μm (A) or wrinkle of wavelength λ = 4-7 μm (B). The elastic moduli ratios of film/substrate were determined using PeakForce quantitative nanomechanical mapping. The characteristic wavelengths (λ) of the patterns for systems A and B were quantitatively estimated in relation to the thickness of the top layer. A diversity of wrinkle morphologies can be achieved by grafting different side chains on pristine PMHS films. The water contact angle (WCA) hysteresis of fluorinated chain (Rf) was enhanced upon roughening the surfaces, giving highly hydrophobic surface properties for water with static/hysteresis WCAs of 136°/74° in the resulting wrinkle (B) and 119°/41° in the dotlike of lower roughness (A). The hydrophobic properties of grafted films on A with various mixtures of hexyl/fluoroalkyl chains were characterized by static CA: WCA 104-119°, ethylene glycol CA 80-96°, and n-hexadecane CA 17-61°. A very low surface energy of 15 mN/m for Rf-PMHS was found on the smoother dotlike pattern.

Asymmetric and nanostructured polystyrene-block-poly(2-vinyl pyridine)-block-poly(ethylene oxide) (PS-b-P2VP-b-PEO or SVEO, S:V:EO ≈ 56:34:10, M ∼ 79.5 kg.mol-1 and Đ ∼ 1.05) thick films blended with 20 wt % of a short PS homopolymer (hPS, M ∼ 10.5 kg.mol-1 and Đ ∼ 1.09) were achieved by combining the non-solvent induced phase separation (NIPS) process with a solvent vapor annealing (SVA) treatment. Here, the NIPS step allows for the formation of a highly-permeable sponge-like substructure topped by a dense thin layer exhibiting poorly-ordered nanopores while the subsequent SVA treatment enables to reconstruct the material top surface into a porous monolayer of well-ordered hexagonal perforated lamellae (HPL). This optimized film architecture generated by NIPS-SVA showed a mean water permeability of 860 L h-1 m-2 bar-1 , which is roughly twice time higher than the flux measured through NIPS made PS-b-P2VP-b-PEO/hPS materials having poorly-ordered nanopores. The post-SVA treatment also revealed as a powerful tool to tailor the thickness of the nanostructure formed within the blended material since monoliths entirely composed of a HPL phase were produced by increasing the time of exposure to a chloroform stream. The water flux of such PS-b-P2VP-b-PEO/hPS monoliths was found to be an order of magnitude lower than that of their asymmetric film homologues. This article is protected by copyright. All rights reserved.

Artificial water channels (AWCs) and their natural aquaporin counterparts selectively transport water. They represent a tremendous source of inspiration to devise biomimetic membranes for several applications, including desalination. They contain variable water-channel constructs with adaptative architectures and morphologies. Herein, we critically discuss the structural details that can impact the performances of biomimetic I quartets, obtained via adaptive self-assembly of alkylureido-ethylimidazoles HC4-HC18 in bilayer or polyamide (PA) membranes. We first explore the performances in bilayer membranes, identifying that hydrophobicity is an essential key parameter to increase water permeability. We compare various I quartets with different hydrophobic tails (from HC4 to HC18), and we reveal that a huge increase in single-channel water permeability, from 10(4) to 10(7) water molecules/s/channel, is obtained by increasing the size of the alkyl tail. Quantitative assessment of AWC-PA membranes shows that water permeability increases roughly from 2.09 to 3.85 L m(-2) h(-1) bar(-1), for HC4 and HC6 reverse osmosis membranes, respectively, while maintaining excellent NaCl rejection (99.25-99.51%). Meanwhile, comparable HC8 loading induces a drop of performance reminiscent of a defective membrane formation. We show that the production of nanoscale sponge-like water channels can be obtained with insoluble, low soluble, and low dispersed AWCs, explaining the observed subpar performance. We conclude that optimal solubility enabling breakthrough performance must be considered to not only maximize the inclusion and the stability in the bilayer membranes but also achieve an effective homogeneous distribution of percolated particles that minimizes the defects in hybrid polyamide membranes.

Self-oscillating filtration membranes having a lifelike pulsatile flow are prepared thanks to a synchronized coupling between a chemical oscillator and a responsive membrane. Commercial alumina membranes are superficially functionalized with pH-responsive poly(methacrylic acid) (PMAA) chains synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization of MAA in the presence of a catechol-based RAFT agent. The grafting of PMAA onto alumina, mediated through catechol chemisorption, is analyzed by X-ray photoelectron spectroscopy, scanning electron microscopy combined with energy-dispersive X-ray spectroscopy, and static water contact angle. Bromate- sulfite-ferrocyanide (BSF) is used as a chemical oscillator, enabling autonomous cyclic pH modulation between 3.5 and 6.5. The pH oscillations are setup in the conditions of membrane filtration inside a filtration cell thanks to a careful study of the bifurcation diagram showing the required conditions to reach the oscillation domain. Since PMAA has a pK(a) around 5.8, a periodic extension-contraction of the polymer chains is obtained during membrane filtration, which leads to a synchronized change in the membrane pore size. Chemically powered autonomous pulsatile flow with an impressive permeability cycles is observed with an effective chemomechanical feedback action of the membrane pore size change on the chemical oscillator mechanism.