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Delamination due to an inferior adhesion between reinforcement material and matrix in carbon fiber-reinforced thermoplastic (CFRTP) composites is a crucial problem to be solved. To this end, this study aims to overcome poor wettability between reinforcing phase, i.e., carbon fiber (CF), and thermoplastic matrix, i.e., polyetherether ketone (PEEK). Herein, CF's surface was tailored by application of different polymeric sizing agents which have different chemical structures. Morphology and topology analyses were performed by Scanning Electron Microscope and 3D laser scanning, respectively. Later, a variety of wettability results were obtained by the sessile drop method used in Contact Angle (CA) measurements for CFs throughout application of each sizing agent applied by dip coating. Sizing materials were designed such that the chemical structure of CF's surface could exhibit compatibility with the matrix itself. Consequently, complete wettability (CA: 0°) was achieved for CFs sized by HPEEK (CF/hydroxylated PEEK (HPEEK)) and the surface free energy (SFE) of CF was enhanced from 5.43 to 72.8 mJ/m2 while the SFE of the PEEK matrix is 40.1 mJ/m2. Moreover, sizing by HPEEK improved the average surface roughness of CF by 32% which enables optimized adhesion. Afterward, repetitive tensile tests were carried out to observe effects of improved interfacial interlocking on the mechanical properties of the final CFRTP composite. Stress–strain curves revealed that the tensile strength of CFRTP improved from 473 to 508 MPa through the sizing of CF by HPEEK whereas pristine PEEK has a much smaller tensile strength (98 MPa) than the aforementioned CF-reinforced composites. The sizing of carbon fiber's surface by HPEEK resulted in an enhanced adhesion with the PEEK matrix. Since the chemical structure and physical properties of sizing agent and matrix are compatible, potential debonding between them was eliminated. Thus, the improved wettability led to a substantial increase in the mechanical strength of the final TP composite. [ABSTRACT FROM AUTHOR]

In this study, sulfur‐enriched microporous organic polymer (MOP) was prepared using one‐pot Shiff‐base type polycondensation reaction of thiophendicarboxaldehyde with melamine. With 195.731 m2 g−1 surface area and 0.047 cm3 g−1 pore volume, the as‐synthesized MOP has a cotton‐like morphology and a micropore‐dominated pore size distribution. After loading MOP with nickel as a co‐catalyst, we demonstrated that the obtained framework could be used as an efficient and robust electrocatalyst for hydrogen evolution reaction (HER) in an alkaline medium with the optimum composite (Ni2@MOP) exhibiting a low onset potential of −66 mV. Furthermore, the optimum electrocatalyst showed good stability, delivering 91% faradaic efficiency (FE) after a 3.5 h chronoamperometry experiment. [ABSTRACT FROM AUTHOR]

We report here the synthesis and characterization of a water dispersible conjugated polymer nanoparticle‐based photosensitizer and its application in the antibacterial and anticancer phototherapies. Nanoparticles (CPPN) were synthesized in one‐pot by nanoprecipitation method, in which a hydrophobic azide functionalized, red‐emitting thiophene‐benzothiodiazole based conjugated polymer (CP‐AZ) was cross‐linked with a hydrophilic, propargylamine functionalized porphyrin (TPP‐4AL) through cucurbit[6]uril (CB6) catalyzed azide‐alkyne cycloaddition (CB6‐AAC) reaction. CPPN demonstrated high stability in aqueous medium for more than a month without any visible aggregation and appeared to be a good photosensitizer with high light‐triggered reactive oxygen species (ROS) generation ability. Consequently, CPPN displayed photo‐induced biocidal activity against Gram‐negative (Escherichia coli, E. coli) and Gram‐positive (Bacillus subtilis, B. subtilis and Staphylococcus aureus, S. aureus) bacteria. When bacteria suspension was incubated with CPPN (20 μg ml−1) and irradiated with white light (22 mW cm−2) for 10 min, more than 3.5‐log reduction in colony‐forming units (CFUs) was recorded for the three model bacteria. CPPN demonstrated minimal dark cytotoxicity against the bacteria. Moreover, the cytotoxicity of CPPN on mammalian cell was studied using MCF‐7 breast cancer cell line. The results demonstrated that CPPN is non‐toxic to mammalian cells in the dark even at a high concentration of 112.5 μg ml−1 and this feature makes CPPN an ideal photosensitizer. [ABSTRACT FROM AUTHOR]

Visible‐light triggerable, stable, organic material‐based photocatalysts that can function in alkaline media without the necessity of sacrificial agent for hydrogen production are highly sought after. Here, we report a novel supramolecular photocatalyst that confers the aforementioned features. This supramolecular photocatalyst (TPP‐4CB7) is synthesized through the conjugation of monohydroxylated cucurbit(7)uril (CB7) hosts to a suitably substituted tetraphenyl porphyrin. Although TPP‐4CB7 by its own preforms as an efficient visible light triggered photocatalyst, the hydrogen production efficiency is significantly enhanced upon mixing with TiO2. The resulting nanocomposite (TPP‐CB‐TiO2@Pt) is observed to exhibit remarkable electrophotocatalytic activity under visible light and produces hydrogen (onset potential −10 mV, turn over frequency (TOF) 0.202 s−1, 24.5 mmol h−1 g−1) from water splitting without any significant degradation during four runs (5 h each) in alkaline media and in the absence of sacrificial agent. [ABSTRACT FROM AUTHOR]

Here we report the preparation of water-dispersible glycosylated poly(2,5′-thienylene)porphyrin based nanoparticles by a nanoprecipitation method and demonstrate the application of these nanoparticles in antibacterial photodynamic therapy. The diameter of the nanoparticles is in the range of 50–80 nm and the resulting nanoparticles are stable in water without precipitation at least for a month. They have high singlet oxygen efficiency and display light-triggered biocidal activity against both Gram negative bacteria (Escherichia coli, E. coli) and Gram positive bacteria (Bacillus subtilis, B. subtilis). Upon white light irradiation for 10 min with a flux of 22 mW cm−2 of the E. coli suspension incubated with NPs (18 μg mL−1), a killing efficiency of 99% is achieved, whereas in the dark the effect is recorded as only around 8%. [ABSTRACT FROM AUTHOR]

In the present work, we describe an efficient filter-based microextraction method with a proper sample clean-up for the simple determination of the banned Sudan dyes (I, II, III, and IV) in the foodstuff and water samples. The method is based upon the dispersion of a low-toxic solidifiable organic solvent (1-undecanol, 75 μL) into an aqueous sample solution and utilization of a syringe filter for the emulsion breaking. This syringe filter with a nylon membrane is compatible with a broad range of solvents and thus is ideal for the rapid filtration of most aqueous and organic solutions. Hence, along with the passage of a mixture of an aqueous sample solution and an organic solvent through the membrane, fine droplets of the extractant solvent are aggregated, separated from the aqueous sample solution. By implementing this simple method, the overall extraction time is just 3-4 min; it is environmentally friendly and centrifuge-free, and it provides a high sample clean-up by filtration of the acceptor phase. The parameters influencing the extraction efficiency including the type and volume of the extraction solvent, pH, ionic strength, and number of extractions are thoroughly examined and optimized. Under the optimal experimental conditions, the proposed method provided a good linearity in the range of 1.0-1500 ng mL−1, good extraction repeatabilities (relative standard deviations below 8.9%, n = 5), low limits of detection (0.2-0.7 ng mL−1), and enrichment factors of 105-138. [ABSTRACT FROM AUTHOR]

A simple, fast, and sensitive method for speciation and determination of As (III, V) and Hg (II, R) in human blood samples based on ionic liquid-dispersive liquid-liquid microextraction (IL-DLLME) and flow injection hydride generation/cold vapor atomic absorption spectrometry (FI-HG/CV-AAS) has been developed. Tetraethylthiuram disulfide, mixed ionic liquids (hydrophobic and hydrophilic ILs) and acetone were used in the DLLME step as the chelating agent, extraction and dispersive solvents, respectively. Using a microwave assisted-UV system, organic mercury (R-Hg) was converted to Hg(II) and total mercury amount was measured in blood samples by the presented method. Total arsenic content was determined by reducing As(V) to As(III) with potassium iodide and ascorbic acid in a hydrochloric acid solution. Finally, As(V) and R-Hg were determined by mathematically subtracting the As(III) and Hg(II) content from the total arsenic and mercury, respectively. Under optimum conditions, linear range and detection limit (3σ) of 0.1-5.0 μg L−1 and 0.02 μg L−1 for As(III) and 0.15-8.50 μg L−1 and 0.03 μg L−1 for Hg(II) were achieved, respectively, at low RSD values of < 4 % (N = 10). The developed method was successfully applied to determine the ultratrace amounts of arsenic and mercury species in blood samples; the validation of the method was performed using standard reference materials. [ABSTRACT FROM AUTHOR]

A sensitive and simple method has been established for simultaneous preconcentration of trace amounts of Pb (II) and Ni (II) ions in water samples prior to their determination by flame atomic absorption spectrometry. This method was based on the using of a micro-column filled with graphene oxide as an adsorbent. The influences of various analytical parameters such as solution pH, adsorbent amount, eluent type and volume, flow rates of sample and eluent, and matrix ions on the recoveries of the metal ions were investigated. Using the optimum conditions, the calibration graphs were linear in the range of 7–260 and 5–85 μg L−1with detection limits (3Sb) of 2.1 and 1.4 μg L−1for lead and nickel ions, respectively. The relative standard deviation for 10 replicate determinations of 50 μg L−1of lead and nickel ions were 4.1% and 3.8%, respectively. The preconcentration factors were 102.5 and 95 for lead and nickel ions, respectively. The adsorption capacity of the adsorbent was also determined. The method was successfully applied to determine the trace amounts of Pb (II) and Ni (II) ions in real water samples. The validation of the method was also performed by the standard reference material. [ABSTRACT FROM AUTHOR]

The front cover artwork for Issue 13/2019 is provided by Tuncel and co‐workers at UNAM and the Chemistry Department of Bilkent University (Turkey). The image shows solar energy promoted photoelectrocatalytic water splitting for hydrogen generation using a supramolecular photocatalyst. See the Communication itself at https://doi.org/10.1002/cctc.201900144. [ABSTRACT FROM AUTHOR]

Front Cover: Novel Supramolecular Photocatalyst Based on Conjugation of Cucurbit[7]uril to Non-Metallated Porphyrin for Electrophotocatalytic Hydrogen Generation from Water Splitting (ChemCatChem 13/2019) B The Front Cover b shows solar energy promoted photoelectrocatalytic water splitting for hydrogen generation using a supramolecular photocatalyst. In their Communication, Dönüs Tuncel and co-workers synthesize a novel, visible light triggerable, stable supramolecular photocatalyst based on conjugation of cucurbit[7]uril to non-metallated porphyrin. [Extracted from the article]