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Highly dispersed poly(amic acid) salt-stabilised palladium nanoparticles(PdNPs/PAAS) were synthesised via a facile reduction strategy in aqueous media at room temperature and characterised by transmission electron microscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and inductively coupled plasma optical emission spectrometer. The nanoparticles were used as catalyst for Suzuki-Miyaura coupling reaction to synthesise biphenyl compounds in short reaction time and high yields under mild conditions, benefiting from highly efficient quasi-homogeneous catalytic activity. The catalyst could be recycled 5 times without obvious loss attributing to the pH response of the PAAS. [ABSTRACT FROM AUTHOR]

A series of polyimide composites with various mass fractions of multi-walled carbon nanotubes (MWNTs) were prepared by in situ polymerization. To increase the chemical compatibility of carbon nanotubes with the polyimide matrix, MWNTs were treated with an acid mixture and sulfoxide chloride in turn. The modified MWNTs are dispersed homogeneously in the matrix while the structure of the PI and MWNTs are stable in the preparation process. The composite films hold preferable thermal stability the same as the pure PI. The composite films exhibited good thermomechanical properties. The storage modulus increased significantly by increasing MWNT content and decreasing the enhancement of temperature. The films’ glass transition temperature increased with enhancing of MWNTs frictions. The dielectric constants of the composites decrease with increasing frequency and increase sharply with the adding of MWNTs, which is favorable for practical use in anti-static materials and embedded capacitors. [ABSTRACT FROM PUBLISHER]

Development of highly active and recyclable catalysts for selective hydrogenation of nitroarenes to amines in water at room temperature is always a challenge in chemical industry. This study reports a facile in situ method for synthesis of ultrafine palladium and platinum nanoparticles (NPs) stabilized by poly (amic acid) salt (PAAS) and their potential as catalysts for hydrogenation of nitroarenes with sodium borohydride or molecular hydrogen as reductant in water at room temperature. In the reduction of 4‐nitrophenol to 4‐aminophenol by sodium borohydride, the activity parameters of PdNPs–PAAS and PtNPs–PAAS catalyst is 6.66 × 103 and 5.58 × 103 s−1 M−1 respectively. In the hydrogenation of diverse nitroarenes under atmospheric hydrogen pressure, PdNPs–PAAS shows high activity but poor selectivity toward desired amines in some cases, while PtNPs–PAAS shows both high activity and high selectivity for selective hydrogenation of nitroarenes to corresponding anilines. The high efficiency of nanocatalyst is due to the quasi‐homogeneous dispersion of metal NPs and synergistic effects between metal NPs and PAAS. In addition, nanocatalyst can be easily recovered with pH‐sensibility of PAAS and reused at least six times without significant loss of catalytic activities. Poly (amic acid) salt (PAAS)‐mediated Pd and Pt NPs have been studied in the catalytic hydrogenation of nitro‐compounds in water at ambient conditions, with high activities and high‐performance, pH‐responsive recyclability and reusability. In particular, the PtNPs–PAAS catalyst combines a good activity and a high selectivity for target amines, without hydrogenation intermediates and by‐products detected in the final products. The high efficiency is mainly due to the quasi‐homogeneous dispersion of metal NPs and the synergistic effects between metal NPs and PAAS. [ABSTRACT FROM AUTHOR]

Electroreduction of nitric oxide (NO) to NH 3 (NORR) has gained extensive attention for the sake of low carbon emission and air pollutant treatment. Unfortunately, NORR is greatly hindered by its sluggish kinetics, especially under low concentrations of NO. Herein, we developed a chlorine (Cl) vacancy strategy to overcome this limitation over FeOCl nanosheets (FeOCl-V Cl ). Density functional theory (DFT) calculations revealed that the Cl vacancy resulted in defective Fe with sharp d-states characteristics in FeOCl-V Cl to enhance the absorption and activation of NO. In situ X-ray absorption near-edge structure (XANES) and attenuated total reflection-infrared spectroscopy (ATR-IR) verified the lower average oxidation state of defective Fe to enhance the electron transfer for NO adsorption/activation and facilitate the generation of key NHO and NH x intermediates. As a result, the FeOCl-V Cl exhibited superior NORR activities with the NH 3 Faradaic efficiency up to 91.1 % while maintaining a high NH 3 yield rate of 455.4 μg cm -2  h -1 under 1.0 vol % NO concentration, competitive with those of previously reported literatures under higher NO concentration. Further, the assembled Zn-NO battery utilizing FeOCl-V Cl as cathode delivered a record peak power density of 6.2 mW cm -2 , offering a new route for simultaneous NO removal, NH 3 production, and energy supply., (© 2023 Wiley-VCH GmbH.)

[structure: see text] 3,5,7-Tris(arylmethyl)-1-aza-adamantanetrione donor-sigma-acceptor compounds have been synthesized in four steps. Computational and (1)H NMR analyses rationalize the solubility, gelation, and conformational properties of the C3-symmetric molecules toward employing sigma-coupled donor-acceptor interactions in molecular self-assembly.