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The objective of this study is to fabricate porosity-controlled polyethylene terephthalate porous materials using a CO2-assisted polymer compression (CAPC) method. In a previous study, the CAPC method was used to fabricate porous polymer materials by compressing fabric sheets in the presence of CO2. However, the controllability of the porosity was not clear in the previous study. In this study, it is shown that the porosity of porous polymer materials could be easily controlled by adjusting the operating conditions of the CAPC method, using polyethylene terephthalate (PET) nonwoven fabric sheets. Using mercury porosimetry, a decrease in the porosity induced by compression accompanied by a decrease in the pore size is demonstrated. Scanning electron micrographs strongly indicate the plasticization of PET fibers by CO2.

Polysulfone (PSF)/fluorinated ethylene propylene (FEP) mixed matrix membranes (MMMs) with super hydrophobic surface were successfully fabricated via non-solvent induced phase separation (NIPS) method. The effects of FEP content on the morphology, roughness, wettability, pore size, and mechanical property of PSF/FEP MMMs were characterized by scanning electron microscope, confocal microscopy, contact angle goniometer, mercury porosimetry, and tensile testing instrument, respectively. When the FEP content was 9 wt%, the average roughness of M-4 reached 0.712 μm. Meanwhile, the water contact angle (CA) and the water sliding angle (SA) was 153.3° and 6.1°, respectively. M-4 showed super hydrophobicity with a micro- and nanoscale structure surface. Then, M-4 was used for separating of water-in-oil emulsion, showing high separation efficiency for water-in-kerosene and water-in-diesel emulsions of 99.79% and 99.47%, respectively. The flux and separation efficiency changed slightly after 10 cycles. Therefore, this study indicated that the obtained PSF/FEP MMM with super hydrophobic surface could be used for efficient water-in-oil emulsion separation.

Organic aerogels are a class of material most suited for their transformation into electrically conducting porous carbon networks. Typically, polymeric aerogels are prepared via base- or acid-catalyzed polymerization of organic monomers. In this work, we report the first synthesis of graphene oxide (GO) induced gelation of poly(urethane–amide) networks which upon pyrolysis yield monolithic N-doped amorphous carbon/reduced GO (rGO) aerogels. Here GO plays a significant multifunctional role of (i) inducing the gelation of poly(urethane–amide) networks; and (ii) tailoring the physical properties of N-doped amorphous carbon–rGO aerogels. The resulting aerogels were characterized by X-ray diffraction (XRD), N2 sorption porosimetry, X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), Fourier-transform Raman spectroscopy (FT-Raman), field emission scanning electron microscopy (FE-SEM), and high resolution transmission electron microscopy (HR-TEM) which support the formation of a highly porous carbon/rGO network. Importantly, the obtained N-doped amorphous carbon/rGO aerogels (0.76 wt% of GO) are electrically conducting with a pore volume, pore diameter and surface area of 0.39 cm3 g−1 (69% mesopores), 36 nm and 260 m2 g−1 respectively. The significantly enhanced specific capacitance is derived from the tailored 3-D mesoporous structure of the N-doped amorphous carbon/rGO aerogels which consist of large pore volumes and a predominant number of accessible mesopores allowing a low resistance path for inward and outward diffusion of electrolyte ions and endowing a high charge storage capability resulting in a superior specific capacitance of 260 F g−1. The nanoporous networks in the as-prepared N-doped amorphous carbon/rGO serve as channels for quick ionic and electronic conduction. In addition to the enhanced physical properties achieved by addition of a minimal amount of GO, the increased specific capacitance can also be credited to the effective N-doping in ACGA-2 resulting in alteration of the electronic structure of rGO with an increase in charge carrier density, and modification of interfacial and quantum capacitance.

A nanocomposite of polyaniline formed within ionic liquid derived ordered mesoporous carbon (PANi@IOMC) was prepared by polymerization of aniline in the presence of IOMC for electrochemical capacitors. The morphology and structure of the nanocomposite were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and porosimetry. To fabricate the supercapacitor electrode, an appropriate mixture of the PANi@IOMC nanocomposite and activated carbon was sonicated in acetone, and then the resulting dispersion was coated on the carbon fiber paper using a spray-coating technique. Because of the relatively high surface area of the nanocomposite for faradaic redox reactions, a maximum specific capacitance of 542 F g−1 in addition to 85% specific capacitance retention after 1000 successive charge–discharge cycles were obtained. The excellent electrochemical performance of the nanocomposite compared to the pure PANi or IOMC, was attributed to the covalent bonding between PANi and the carbon structure in the presence of N-phenyl-p-phenylenediamine (NPP) as an initiator for linking the polymer chains to the surface. The results of the present work highlight the efficiency of the interfacial chemistry of NPP in generating the nanocomposite with enhanced conductivity and high surface area.

Nano Ag/ZnO is successfully synthesized by a new simple and low cost method employing Zn(NO3)2·6H2O, AgNO3, and urea. X-ray diffraction (XRD), transmission electron microscopy (TEM), adsorption/desorption porosimetry (BET) and X-ray photoelectron spectroscopy (XPS) were used to characterize the structure and morphology of the catalyst. The amount of Ag loading on ZnO (9.276 × 10−5, 7.391 × 10−5, 3.632 × 10−5, and 3.286 × 10−5 mol%) was determined by induced coupled plasma (ICP). The resulting ZnO-supported Ag nanoparticles efficiently catalyzed the oxidation reactions of alkyl-substituted benzenes with hydrogen peroxide (H2O2) as a cheap and environmentally friendly oxidant under solvent-free conditions. This catalytic reaction gave good to excellent yield of products by using mild reaction conditions and no additives were employed during the reaction.

Micellar-enhanced ultrafiltration (MEUF) is a promising technology to remove organic contaminants from wastewater. A laboratory experiment was carried out to study the performance of four Gemini surfactant systems (CG12, CG16, CG12 + Brij35, CG16 + Brij35) for treating synthetic wastewater. The results show that CG16–Brij35 possesses the lowest flux behavior and the best rejection efficiencies toward phenol and surfactants. Pore blocking models are utilized to estimate membrane fouling of surfactant systems. For CG12 and CG12 + Brij35 systems, internal pore blocking, intermediate pore blocking and cake formation models occur simultaneously. Internal pore blocking and cake formation are the main fouling mechanisms of CG16 micelles. With respect to CG16–Brij35, cake layer is the main type of fouling mechanism. The increased pore blocking degree follows the order of CG12 < CG16 < CG12 + Brij35 < CG16 + Brij35. Furthermore, SEM, ATR-FTIR and a mercury porosimeter are used to analyze membrane surface morphology, membrane material characteristics and membrane fouling layer, as well as examine and verify fouling mechanisms. Due to high flux behavior, excellent phenol rejection and low membrane fouling, CG12 is a more desirable selection. Studies output helps to understand the fouling mechanism of MEUF in the presence of Gemini surfactants, and gave valuable evidence to optimize operation strategies.

Single-crystalline bismuth titanates (Bi12TiO20) with the cubic phase and various morphologies (flower-, belt-, tetrahedral-like) were controllably fabricated by using a mild template-free hydrothermal process. The samples were fully characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution TEM, nitrogen porosimetry measurement, UV-vis diffuse reflectance spectroscopy (DRS), and X-ray photoelectron spectroscopy (XPS). The influence of the solvent and the concentration of NO3− in the reaction system on the crystallinity and morphology of the Bi12TiO20 samples was investigated in detail. Bi12TiO20 crystals were used as the sunlight-driven photocatalysts to degrade aqueous dye methyl orange (MO) and p-nitrophenol (PNP), and the influence of Bi12TiO20 morphology on the photocatalytic activity was discussed. Finally, the recyclability of Bi12TiO20 was evaluated through three consecutive runs.

The controlled pyrolysis of mesoporous polysaccharide-derived materials, from starch and alginic acid, formed carbonaceous materials (Starbons®) and were demonstrated as efficient materials for the removal of dyes from wastewater. The resulting materials were characterised by solid-state NMR, N2 adsorption porosimetry, FT-IR, scanning electron microscopy (SEM) and tunnelling electron microscopy (TEM). The material’s efficiency for dye adsorption was tested using methylene blue (MB) and acid blue 92 (AB) dyes. Adsorption data indicated that the mesoporosity of the material had a far greater influence on the adsorption capacity and speed of adsorption, than high surface area alone. Mesoporous Starbon® (A300) was evaluated against commercially available activated carbon (Norit) and demonstrated a superior adsorption capacity of MB; 186 mg g−1vs. 42 mg g−1. The kinetic activity of Starbon® was also determined with A800 showing the fastest rate of adsorption compared to S800 and Norit, suggesting that it is a more suitable material for water purification.

Mesoporous silica films with vertically aligned hexagonal pores have been produced via the electrochemically assisted surfactant assembly (EASA) method using cetyltrimethylammonium bromide (CTAB) surfactant. Mesoporous silica powder has also been synthesised using the same surfactant. The pore walls of the silica powder and films have been grafted with organosilane reagents. The size of the pore, degree of grafting and effect on the properties of the pore have been investigated using porosimetry, contact angle, NMR and CHN analysis. The degree of grafting was found to be dependent upon the size of the grafting agent, with the smallest steric bulk grafting most effectively. It was found that the grafting of the pores with Me3SiCl greatly increased the hydrophobicity of the pore and reduced water penetration. Grafting with larger groups caused the film surface to be hydrophobic but had little effect on the penetration of water into the pores.

Xylose is a major component of hemicelluloses. In this paper, its hydrogenation to xylitol in aqueous medium was investigated with two Ru/TiO2 catalysts prepared with two commercial TiO2 supports. A strong impact of support on catalytic performances was evidenced. Ru/TiO2-R led to fast and selective conversion of xylose (100 % conversion in 2 h at 120°C with 99 % selectivity) whereas Ru/TiO2-A gave a slower and much less selective transformation (58 % conversion in 4 h at 120°C with 17 % selectivity) with the formation of several by-products. Detailed characterization of catalysts with ICP, XRD, FTIR, TEM, H2 chemisorption, N2 porosimetry, TPR and acid-base titration were performed to elucidate the role of each support. TiO2-R has a small specific surface area with large ruthenium nanoparticles in weak interaction with TiO2 support and no acidity, whereas TiO2-A is a mesoporous material with a large specific surface area, mildly acidic, and bears small ruthenium particles in strong interaction with TiO2 support. The former was very active and selective for xylose hydrogenation to xylitol whereas the latter was less active and poorly selective. Moreover, careful analysis of reaction products also revealed that TiO2 anatase can catalyze undesired side-reactions such as xylose isomerisation to various pentoses, and therefore the corresponding unexpected polyols (arabitol, ribitol) were produced during xylose conversion by hydrogenation. In a first approach of the kinetics, a simplified kinetic model was built to compare quantitatively intrinsic reaction rates of both catalysts. The kinetic constant for hydrogenation was 20 times higher for Ru/TiO2-R at 120°C.

This paper manifests an A3-coupling strategy assisted by novel hydromagnesite sheets impregnated with cobalt ferrite (CoFe2O4-HMS) magnetic nanoparticles (MNPs) as an environmentally benign nanocomposite to synthesize imidazo[1,2-a]pyridine scaffolds under ultrasonication. The synthesis of these biologically active derivatives was achieved through A3-coupling employing 2-aminopyridines derivatives, pertinent aryl aldehydes, and phenylacetylene in the presence of polyethylene glycol 400 (PEG 400) as a green solvent under aerobic conditions. Based on its high product yield (up to 94%) in a short reaction time, with a modest catalyst loading, excellent catalyst, and solvent recyclability without substantial loss of operation (up to five synthetic cycles), as demonstrated by the high ecological compatibility and sustainability factors, this strategy follows the principles of green chemistry. The synthesized nanocomposite was characterized via several spectroanalytical techniques, including PXRD, FE-SEM, HR-TEM, EDAX, ICP-AES, FT-IR, Raman spectroscopy, CO2-TPD, TGA-DTA-DTG analyses, magnetic studies, and nitrogen porosimetry. Furthermore, the structures of synthesized compounds were confirmed based on FT-IR, 1H NMR, 13C NMR, mass spectroscopy, and elemental analysis data.

The mechanism of seeding of zeolite BEA via steam assisted conversion has been studied using BEA seeds with different composition. The catalysts are characterized by X-ray diffraction, scanning and transmission electron microscopy, nitrogen adsorption–desorption, Hg-porosimetry, X-ray fluorescence and TPD of ammonia, and evaluated in benzene alkylation with propene. The results show that variation of the SiO2/Al2O3 ratio from 25 to 250 in BEA seeds changes the mechanism of seeding from “core–shell” to a “dissolution” mechanism, which can serve as a tool for engineering the morphological, textural and catalytic properties of BEA zeolites. Al-rich seeds (SiO2/Al2O3 = 25) do not dissolve during gel preparation and initiate dense oriented crystal growth on their surface resulting in the formation of large polycrystals (1–2 μm) with ordered densely intergrown nanocrystallites. In contrast, Si-rich seeds (SiO2/Al2O3 = 250) dissolve into tiny fragments, which serve as individual nuclei leading to formation of tiny isolated nanocrystallites aggregated into small hierarchical aggregates with high intercrystalline mesoporosity. The decrease of particle size and formation of intercrystalline mesoporosity in hierarchical aggregates improves the accessibility of acidic sites and facilitates the diffusion of reaction products, which leads to the significant improvement of catalytic activity and reduces the deactivation resulting in higher stability with time on stream in cumene synthesis from benzene and propylene.

A polymerized high internal phase emulsion (polyHIPE) was prepared using styrene, divinylbenzene and butyl acrylate as raw material and employed as stationary phase of thin layer chromatography (TLC). SEM, mercury intrusion porosimetry and FT-IR spectrum were employed to characterize the pore structure and chemical composition. To verify the feasibility as stationary phase of TLC, identification of plant extracts, Chinese herbs and traditional Chinese medicine were practiced on the prepared polyHIPE. Relative retardation factor (α), theoretical plate number (Nplate) and resolution (R) were used to evaluate the performance of TLC. Large difference in α value make it is feasible to optimize the chromatographic condition. The resolution R and Nplate indicates that the introduction of BA in polyHIPE facilitates the preparation and improves the performance for TLC separation. Our results show that polyHIPE monolith is a reusable stationary phase of TLC with high performance.

A novel strategy for the rapid and selective extraction of ribosylated metabolites by dopamine assisted functionalization of boronic acid on magnetic (Fe3O4@PDA-FPBA) nanoparticles has been demonstrated under optimized conditions. The study is designed to overcome the drawbacks of dendrimer assisted functionalization of low molecular weight cis-diol compounds, in combination with the advantages of boronic acid affinity towards nucleosides. Magnetic particles provide rapid extraction processing, polydopamine contributes in achieving better functionalization of boronic acid on magnetic particles because of the presence of multiple active sites at terminal groups and boronic acid selectively captures cis-diol compounds via reversible covalent bonding. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirm the particle size (80–120 nm). Energy dispersive X-ray spectroscopy (EDS) justifies the elemental composition of the material. The BET surface area (64 m2 g−1) is obtained from nitrogen adsorption porosimetry and coating of polydopamine and boronic acid is confirmed by Fourier transform infra-red (FT-IR) spectroscopy. Fe3O4@PDA-FPBA is highly selective with better adsorption capacity (197.3, 183.9, 163.1 and 186.5 μg g−1 for adenosine, cytidine, guanidine and uridine respectively) and recovery for ribosylated metabolites ranging from 87 to 133% for different standards. The magnetic sorbent also extracts 47 endogenous nucleoside metabolites from urine samples of healthy and lung cancer patients. Magnetic separation, combined with superior performance as compared to previously reported materials, makes Fe3O4@PDA-FPBA a promising addition to targeted metabolites analysis.

Frontal polymerization was successfully utilized, for the first time, to obtain pH/temperature-sensitive hydrogel-based molecularly imprinted polymers (hydroMIPs). The polymerization reaction can be completed in 20 min. By this approach, hydroMIPs were synthesized using a mixture of gatifloxacin (template), N-isopropylacrylamide, acrylic acid and N,N′-methylenebisacrylamide. The influence of template concentration and the crosslinker amount on the imprinting effect of the hydroMIPs was investigated. The textural and morphological parameters of the hydroMIPs were also characterized by mercury intrusion porosimetry, DSC, and scanning electron microscopy. The gatifloxacin-imprinted polymer formed in frontal polymerization displayed high affinity than conventional thermal polymerization. The hydroMIPs were further evaluated as drug delivery devices and showed higher relative bioavailability than the corresponding non-imprinted polymer and hydroMIPs based on bulk polymerization from the results of the evaluation in vivo. The results suggest that frontal polymerization provides an alternative method to prepare hydroMIPs and may open up new perspectives in the field of MIPs.

A facile and fast procedure has been developed to prepare one-dimensional (1D) hybrid microchains by sintering of Fe3O4/poly(styrene-co-n-butyl acrylate-co-acrylic acid) (Fe3O4/P(St-co-nBA-co-AA)) hybrid microspheres. Noteworthily, it is the first time that the 1D structure has been linked and fixed via physical fusion instead of by a chemical method. The crucial process is to sinter the hybrid microspheres at the glass transition temperature (Tg) of P(St-co-nBA-co-AA) particles under a magnetic field. SEM, optical microscopy, EDS, XRD and FTIR have proved the successful fabrication of 1D Fe3O4/P(St-co-nBA-co-AA) hybrid microchains and the formation mechanism has been discussed. The 1D hybrid microchains have lengths of several hundred micrometers and diameters of 10–15 μm. A TGA measurement has indicated that the large proportion of fused polymer particles in the 1D structures reaches 64.5%. A VSM curve has shown that the saturation magnetization is 18.7 emu g−1, which is enough for the 1D microchains to be controlled and separated by the external magnetic field. Mercury intrusion porosimetry and a SEM image of the fractured 1D microchains have demonstrated that these microchains are porous. Moreover, it has been found that individual microchains can be obtained at a low concentration of Fe3O4 particles, otherwise aggregation occurs.