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The use of two polycarboxylic acids(PCAs), such as 1,2,3,4-butanetetracarboxylicacid (BTCA) and citric acid (CA), was employed to esterify handsheetsprepared from thermomechanical pulp (TMP) fibers. Sodium hypophosphitewas used as a catalyst. The Fourier transform infrared (FTIR) spectrometrytechnique was utilized to verify the ability of these PCAs to formester functions between the fibers. The modifications of both thetemperature and the mass amount of the PCA were investigated. Finally,the wet breaking length of the prefabricated and cured handsheetswas measured and an improvement was observed in both cases. The raiseof the mass amount increased the wet breaking length for the two cases.On the other hand, a comparison between the two PCAs was carried out.For the same mass amount, BTCA was more effective to cross-link theTMP fibers at high temperature while CA showed slightly better resultsat low temperature. [ABSTRACT FROM AUTHOR]

A layer-by-layer (LbL) self-assembly technique using polyallylamine hydrochloride (PAH) and polyacrylic acid (PAA) was employed to build up polyelectrolyte multi-layers on pretreated thermomechanical pulp fibres. These pretreated fibres previously had been oxidized by means of a 4-acetamido TEMPO-mediated process in order to create carboxylic functions. These allow the subsequent formation of amide bonds between PAH and fibres. X-ray photo-electronic spectroscopy (XPS) analyses confirmed the formation of amide bonds between the carboxylic function on the fibres and the primary amine function of the PAH. Besides, the surface charge intensity of the coated fibres was determined by measuring the zeta potential after each treatment step. [ABSTRACT FROM AUTHOR]

The atomic force microscope (AFM) can be used to perform surface force measurements in the quasi-static mode (cantilever is not oscillating) to investigate nanoscale surface properties. Nevertheless, there is still a lack of literature proposing a complete systematic and rigorous experimental procedure that enables one to obtain reproducible and significant quantitative data. This article focuses on the fundamental experimental difficulties arising when making force curve measurements with the AFM in air. On the basis of this AFM calibration procedure, quantitative assessment values were used to determine, in situ, SAM (or Self Assembled Monolayer)-tip thermodynamic work of adhesion at a local scale, which have been found to be in good agreement with quoted values. Finally, determination of surface energies of functionalised silicon wafers (as received, CH 3 , OH functionalised silicon wafers) with the AFM (at a local scale) is also proposed and compared with the values obtained by wettability (at a macroscopic scale). In particular, the effect of the capillary forces is discussed. [ABSTRACT FROM AUTHOR]

In this study, we propose a practical approach for producing a heterobimetallic Ni(II)-Ce(III) diimine complex from an extended salen-type ligand (H 2 L) to serve as an electrocatalyst for CO 2 reduction and demonstrate an outstanding overall efficiency of 99.6% of the cerium-nickel complex and integrate it into applicable cell assemblies. We optimize not only the catalyst, but the operational conditions enabling successful CO 2 electrolysis over extended periods at different current densities. A comparison of electrochemical behavior in H-cell and zero-gap cell electrolyzers suggests potential applications for industrial scale-up. In the H-cell electrolyzer configuration, the most elevated efficiency in CO production was achieved with a selectivity of 56.96% at -1.01 V vs RHE, while HCOO - formation exhibited a selectivity of 32.24% at -1.11 V vs RHE. The highest TON was determined to be 14657.0 for CO formation, followed by HCOO - with a TON of 927.8 at -1.11 V vs RHE. In the zero-gap electrolyzer configuration, the most efficient setup toward CO production was identified at a current density (CD) of 75 mA cm -2 , a flow rate of 10 mL min -1 , operating at 60 °C and utilizing a low KOH concentration of 0.1 M to yield a maximum faradaic efficiency (FE CO ) of 82.1% during 24 h of stable electrocatalysis., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

As alternative energy sources are essential to reach a climate-neutral economy, hydrogen peroxide (H 2 O 2 ) as futuristic energy carrier gains enormous awareness. However, seeking for stable and electrochemically selective H 2 O 2 ORR electrocatalyst is yet a challenge, making the design of-ideally-bifunctional catalysts extremely important and outmost of interest. In this study, we explore the application of a trimetallic cobalt(II) triazole pyridine bis-[cobalt(III) corrole] complex Co II TP[Co III C] 2 3 in OER and ORR catalysis due to its remarkable physicochemical properties, fast charge transfer kinetics, electrochemical reversibility, and durability. With nearly 100 % selective catalytic activity towards the two-electron transfer generated H 2 O 2 , an ORR onset potential of 0.8 V vs RHE and a cycling stability of 50 000 cycles are detected. Similarly, promising results are obtained when applied in OER catalysis. A relatively low overpotential at 10 mA cm -2 of 412 mV, Faraday efficiency 98 % for oxygen, an outstanding Tafel slope of 64 mV dec -1 combined with superior stability., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)