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Herein, CoN4, CuN4, and NiN4 complexes with a 14-membered ring hexaazamacrocycle ligand H2HAM were synthesised as precursors for ORR and CO2RR catalysts via a one-pot, gram-scale synthesis procedure, which involved microwave heating for only 10 min. Detailed structures of the obtained 14MR-MN4 complex were revealed by single-crystal X-ray diffraction measurements. [ABSTRACT FROM AUTHOR]

A new series of benzobisthiadiazole (BBT)-based donor–acceptor copolymers, namely, PBBT-FT, PBBT-T-FT, and PBBT-Tz-FT, with different π-conjugated bridges have been developed for polymer thin film transistors (TFTs). It was found that inserting different π-conjugated bridges into the backbone of the polymer allowed tailoring of opto-electrical properties, molecular organizations, and accordingly, ambipolar transport of TFTs. The UV-vis-NIR spectra of all three polymers were similar with the low band gaps of around 1.1 eV. While the lowest unoccupied molecular orbital (LUMO) energy levels were also similar (around −3.8 eV), the highest occupied molecular orbital (HOMO) energy levels varied from −5.05 to −5.42 eV because of the different π-conjugated bridges; moreover, their TFTs exhibited different ambipolar transport. p-Type dominant TFT performances with the hole mobility (μh) reaching 0.13 cm2 V−1 s−1 were observed for the prototype polymer PBBT-FT. However, the device based on PBBT-T-FT with thiophene bridges displayed lower but more balanced hole (μh) and electron (μe) mobilities of 6.5 × 10−3 and 1.2 × 10−3 cm2 V−1 s−1, respectively. The device based on PBBT-Tz-FT with the thiazole units exhibited more evenly balanced hole and electron mobilities (μh/μe = 0.45) along with a significantly enhanced μe∼0.02 cm2 V−1 s−1. These different semiconducting features were ascribed to different molecular orientations and film morphologies revealed by wide-angle X-ray scattering (WAXS) and atomic force microscopy (AFM). [ABSTRACT FROM AUTHOR]

A high performance Pt-free cathode catalyst for polymer electrolyte fuel cells has been synthesized by the multi-step pyrolysis of polyimide fine particles with a diameter of about 100 nm. This cathode catalyst exhibits good fuel cell performance (1.0 A cm-2 at 0.6 V and 80 °C) along with promising durability. [ABSTRACT FROM AUTHOR]

A series of poly(phenylene ether)s with sulfonic acid groups via long alkyl side chains, SPPEs, were successfully prepared as proton exchange membranes for fuel cells. The new monomer, bis[4-fluoro-3-(p-methoxylbenzoyl)]biphenyl (BFMBP), containing two pendent methoxyphenyl groups was synthesized by the Friedel–Crafts reaction of 5-chloro-2-fluorobenzoyl chloride with anisole, followed by the nickel-mediated homocoupling reaction. Poly(phenylene ether)s (PPEs) were then successfully obtained by the aromatic nucleophilic substitution polycondensation of BFMBP with dihydroxy-monomers in the presence of potassium carbonate. Sulfonated PPEs (SPPEs) (IEC: 1.96–2.45 mequiv. g−1) could be prepared by the reaction of PPEs containing phenol units with 1,4-butanesultone. By the solution casting method, SPPEs produced transparent membranes with good mechanical properties, and showed good oxidative and dimensional stabilities, and high proton conductivities, e.g., 8.60 × 10−3 S cm−1 under 30% relative humidity at 80 °C, which is higher than that of Nafion 117. [ABSTRACT FROM AUTHOR]

An expedient, non-metallic green protocol for aerobic oxidation of alcohols was established. 1-Methyl-2-azaadamantane N-oxyl was used as the core catalyst due to its superior chemical stability and catalytic performance. The catalyst can be easily reused through phase separation by taking advantage of its solubility feature, which varies with its oxidation state. [ABSTRACT FROM AUTHOR]

Herein, CoN 4 , CuN 4 , and NiN 4 complexes with a 14-membered ring hexaazamacrocycle ligand H 2 HAM were synthesised as precursors for ORR and CO 2 RR catalysts via a one-pot, gram-scale synthesis procedure, which involved microwave heating for only 10 min. Detailed structures of the obtained 14MR-MN 4 complex were revealed by single-crystal X-ray diffraction measurements.

An instrumentation technique for real-time, in situ and real space observation of microphase separation was proposed for ultra-high molecular weight block copolymer thin films (1010 kg mol -1 , domain spacing of 180 nm) under high solvent vapor swelling conditions. This is made possible by a combination of a homebuilt chamber which is capable of supplying sufficient amount of vapor, and force-distance curve measurements which gives real-time swollen film thickness and allow active feedback for controlling the degree of swelling. We succeeded in monitoring the domain coarsening of perpendicular lamellar structures in polystyrene- block -poly(methyl methacrylate) thin films for eight hours via tapping mode imaging. During the annealing process, the thickness reached a maximum of 8.5 times that of the original film. The series of temporal real space topographic images obtained via this method allowed us to study, for the first time, the growth exponent of the correlation length under solvent vapor annealing., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)