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A series of cross‐linked AEMs (c‐DQPPO/PVA) are synthesized by using rigid polyphenylene oxide and flexible poly(vinyl alcohol) as the backbones. Dual cations are grafted on the PPO backbone to improve the ion exchange capacity (IEC), while glutaraldehyde is introduced to enhance compatibility and reduce swelling ratio of AEMs. In addition to the enhanced mechanical properties resulting from the rigid‐flexible cross‐linked network, c‐DQPPO/PVA AEMs also exhibit impressive ionic conductivity, which can be attributed to their high IEC, good hydrophilicity of PVA, and well‐defined micro‐morphology. Additionally, due to confined dimension behavior and ordered micro‐morphology, c‐DQPPO/PVA AEMs demonstrate excellent chemical stability. Specifically, c‐DQPPO/PVA‐7.5 exhibits a wet‐state tensile strength of 12.5 MPa and an elongation at break of 53.0 % at 25 °C. Its OH− conductivity and swelling degree at 80 °C are measured to be 125.7 mS cm−1 and 8.2 %, respectively, with an IEC of 3.05 mmol g−1. After 30 days in a 1 M NaOH solution at 80 °C, c‐DQPPO/PVA‐7.5 experiences degradation rates of 12.8 % for tensile strength, 27.4 % for elongation at break, 14.7 % for IEC, and 19.2 % for ion conductivity. With its excellent properties, c‐DQPPO/PVA‐7.5 exhibits a peak power density of 0.751 W cm−2 at 60 °C in an H2‐O2 fuel cell. [ABSTRACT FROM AUTHOR]

AuCo alloys were prepared by magnetron sputtering for the first time without considering the insolubility on the phase diagram. The electronic effect between Au and Co can change the oxygen adsorption energy and the ORR activity. The ORR activity of the Au46Co54 alloy electrode not only exceeded that of Au, but also exceeded that of Pt in basic solution. [ABSTRACT FROM AUTHOR]

Nano-network Ru with definite lattice defects on amorphous Co nanosheets is obtained for the first time. Amorphous Co support can promote the surface Ru to obtain special morphology and modified electronic structure, thus improving HER activity in alkaline solution. A current density of 10 mA cm−2 can be obtained only with an overpotential of 33.5 mV. [ABSTRACT FROM AUTHOR]

Food-borne diseases are widespread all over the world, and food safety has attracted much attention. This study is the first to use plasma to activate acidic electrolyzed water (AEW) to obtain a new disinfectant for food processing. The germicidal efficacy of plasma-activated acidic electrolyzed water (PA-AEW) on B. subtilis suspension and biofilm was investigated. Furthermore, the synergistic effect of different bactericidal factors was inferred by investigating the physicochemical parameters of PA-AEW and the influencing factors of bactericidal effect. The results demonstrate that PA-AEW is a highly effective and rapid disinfectant. The killing logarithm (KL) value of PA-AEW on B. subtilis suspension could reach 2.33 log10CFU/mL with a sterilization time of 10 s, which is significantly higher than that of AEW (KL = 0.58 log10CFU/mL) and plasma-activated water (PAW) (KL = 0.98 log10CFU/mL) (significant difference, p < 0.01). Moreover, the KL value of the B. subtilis biofilm of PA-AEW was 2.41 log10CFU/mL, better than that of PAW and AEW (significant difference, p < 0.01), indicating that PA-AEW has important application prospects in food processing. The synergistic effect should come from the interaction between reactive chlorine species (RCS) and reactive oxygen and nitrogen species (RONS) in PA-AEW. [ABSTRACT FROM AUTHOR]

RuCo-ANFs with different proportions can be successfully prepared by magnetron sputtering, and their lattice constants can be adjusted accurately. In the RuCo-ANF, there is an obvious electronic interaction between Ru and Co, thus adjusting the ΔGH* on its surface. There is a volcanic relationship between the HER activity and the lattice constant of RuCo-ANF. [ABSTRACT FROM AUTHOR]

The rise of heterocycle cations, a new class of stable cations, has fueled faster growth of research interest in heterocycle cation‐attached anion exchange membranes (AEMs). However, once cations are grafted onto backbones, the effect of backbones on properties of AEMs must also be taken into account. In order to comprehensively study the influence of cations effect and backbones effect on AEMs performance, a series of AEMs were prepared by grafting spacer cations, heterocycles cations, and aromatic cations onto brominated poly(2,6‐dimethyl‐1,4‐phenylene oxide) (BPPO) or poly(vinylbenzyl chloride) (PVB) backbones, respectively. Spacer cation [trimethylamine (TMA), N,N‐dimethylethylamine (DMEA)]‐attached AEMs showed general ion transportation and stability behaviors, but exhibited high cationic reaction efficiency. Heterocycle cation [1‐methylpyrrolidine (MPY), 1‐methylpiperidine (MPrD)]‐attached AEMs showed excellent chemical stability, but their ion conduction properties were unimpressive. Aromatic cation [1‐methylimidazole (MeIm), N,N‐dimethylaniline (DMAni)]‐attached AEMs exhibited superior ionic conductivity, while their poor cations stabilities hindered the application of the membranes. Besides, it was found that PVB‐based AEMs had excellent backbone stability, but BPPO‐based AEMs exhibited higher OH− conductivity and cation stability than those of the same cations grafted PVB‐based AEMs due to their higher water uptake (WU). For example, the ionic conductivities (ICs) of BPPO‐TMA and PVB‐TMA at 80 °C were 53.1 and 38.3 mS cm−1, and their WU was 152.3 and 95.1 %, respectively. After the stability test, the IC losses of BPPO‐TMA and PVB‐TMA were 21.4 and 32.2 %, respectively. The result demonstrated that the conductivity and stability properties of the AEMs could be enhanced by increasing the WU of the membranes. These findings allowed the matching of cations to the appropriate backbones and reasonable modification of the AEM structure. In addition, these results helped to fundamentally understand the influence of cation effect and backbone effect on AEM performance. [ABSTRACT FROM AUTHOR]

AuIr alloy nanoparticles were successfully prepared without using surfactants for the first time despite Au and Ir being immiscible according to phase diagrams. The lattice parameters of the AuIr alloy can be adjusted arbitrarily. The oxygen reduction reaction (ORR) activity of Au5Ir5 alloy is better than that of Au or Ir, and the oxygen evolution reaction (OER) activity of the Au5Ir5 alloy is as good as that of Ir in alkaline solution. [ABSTRACT FROM AUTHOR]

An obvious H-UPD for a nano AuTiO2−x composite has been found for the first time in terms of the electrochemical characteristics of the Au composite. The electronic effect between Au and TiO2 and the oxygen vacancy defect would change the adsorption energy of H and HER activity. The HER activity of the AuTiO2−x electrode is 6.44 times that of the Au electrode. [ABSTRACT FROM AUTHOR]

Electrolyzed oxidizing water (EO water) bactericide is an indirect electrochemical sterilization technology, which is characterized by broad-spectrum, rapid and powerful sterilization. EO water, with a certain amount of available chlorine content (ACC), is generated by electrolysis of an extremely dilute NaCl solution. It is very important to study the preparation process of EO water, including electrode material and electrolytic process. In this paper, the effect of electrode material (platinum, iridium or ruthenium) on the physical and chemical parameters of EO water was investigated first. The effect of electrode composition and roasting temperature on the ACC of EO water was rigorously analyzed. The sterilization effect of EO water produced by different electrode materials was further discussed. In addition, the accelerated service lifetime of the electrode and exchange electrode polarity electrolysis were also investigated. Next, for the electrolysis process, the effects of ion exchange membrane type, current density and electrolyte concentration on the ACC of EO water, anode current efficiency and energy consumption were also studied. Finally, the stability of EO water, that is, the influence of illumination, heating and stirring on the physical and chemical parameters of EO water, was also observed in detail. [ABSTRACT FROM AUTHOR]

The development of highly active and long-term stable electrocatalysts for the hydrogen evolution reaction (HER) is very important. Because of the hysteresis phenomenon, IrO2 is rarely used as a cathode material for the HER. Herein, an IrO2–TiO2 composite oxide was prepared using the thermal decomposition method. The physical and electrochemical characterization of the materials was achieved by scanning electron microscopy (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). In the process of the HER, the current of IrO2 is only 1.91 mA cm−2@−0.2 V in the first segment scan. However, at the 51, 101 and 151 segment scan, the HER current increases to 6.85, 15.7 and 18.2 mA cm−2@−0.2 V, respectively. During the activation process of IrO2, the HER current has increased ten times. Compared with the HER activity of IrO2, there is almost no hysteresis for the IrO2–TiO2 electrode. In the first segment scan, the HER current has already reached 27.9 mA cm−2@−0.2 V and further increased to 31.1, 33.1 and 35.0 mA cm−2 at the 51, 101 and 151 segment scan. The difference between them is not significant, which means that the IrO2–TiO2 electrode does not need activation. The IrO2–TiO2 electrode has exhibited a higher HER activity than the IrO2 electrode, which may be attributed to the electronic structure modification and the increase of the electrochemical area. [ABSTRACT FROM AUTHOR]

Fluorine doped graphitic carbon nitride (g-C3N4) was successfully synthesized by a convenient co-polycondensation of urea and ammonium fluoride (NH4F) mixtures, and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (FTIR), UV-Vis diffuse reflectance absorption spectra (UV-DRS), nitrogen adsorption-desorption, photoelectrochemical measurement and photoluminescence (PL) spectra. The photocatalytic activities of fluorine doped g-C3N4 samples were evaluated by the degradation of Rhodamine B (RhB) solution under visible light irradiation. The results showed that the fluorine doped g-C3N4 had a better photocatalytic activity than that of undoped g-C3N4, which was attributed to the favorable textural, optical and electronic properties derived from the fluorine atoms substituting nitrogen atoms of g-C3N4 frameworks. The photoelectrochemical measurements confirmed that the charges separation efficiency was improved by fluorine doping g-C3N4. Moreover, the tests of radical scavengers demonstrated that the holes (h) and superoxide radicals (O) were the main active species for the degradation of RhB. The enhanced visible light photocatalytic activity of fluorine-doped graphitic carbon nitride was synthesized by a simple and facile thermal treatment of urea and ammonium fluoride mixtures. The XPS investigation showed that the fluorine atoms substituted nitrogen atoms of g-C3N4 frameworks during the co-condensation process, which favored the enhancement of photocatalytic performance. [ABSTRACT FROM AUTHOR]

The potential ofOsmanthus fragranspowder as a natural biosorbent was investigated for the removal of methylene blue (MB) from aqueous solution. The effects of various experimental conditions including contact time, adsorbent dose, initial MB concentration, solution pH, salt ionic strength, and temperature on the adsorption properties ofO. fragranspowder were discussed. The adsorption kinetic data were modeled using pseudo-first-order, pseudo-second-order, and intraparticle diffusion kinetics equations, indicating that the pseudo-second-order and intraparticle diffusion models could better describe the adsorption kinetics. Furthermore, adsorption equilibrium data were analyzed by Langmuir and Freundlich models, suggesting the Langmuir model presented a better correlation with the experimental data. The maximum adsorption capacities (qm) ofO. fragranspowder for MB obtained from the Langmuir model were 155.52, 165.02, and 172.71 mg g−1at different temperatures of 288.15, 298.15, and 308.15 K, respectively. Thermodynamic parameters such as standard free energy changes (ΔG°), standard enthalpy changes (ΔH°), and standard entropy changes (ΔS°) were also calculated. The results showed that the adsorption process was spontaneous and endothermic in nature. In addition, the possible adsorption mechanism ofO. fragranspowder as adsorbent was proposed. The present study implies thatO. fragranspowder were a promising candidate as novel biosorbents for the removal of MB from aqueous solution. [ABSTRACT FROM AUTHOR]

Combined computational and experimental studies reveal a noble, non-d-band effect on Ag activation and electrocatalysis: upon coating Ag onto the even more inert Au surface, the catalytic activity toward the oxygen reduction reaction in alkaline media can be improved by about half an order of magnitude in comparison to the usual Ag surface. [ABSTRACT FROM AUTHOR]

The Z-scheme photocatalysts of WO 3 /g-C 3 N 4 composites with WO 3 nanoplates anchored on the surface of g-C 3 N 4 were synthesized by in-situ acidic precipitation and following calcination procedure. The resultant photocatalysts were characterized by various analytical techniques. This face-to-face intimate contact between g-C 3 N 4 and plate-like WO 3 not only increases the interfacial contact areas, but also facilitates the transfer and separation of photogenerated charge carriers. The photocatalytic activities of degradation Rhodamine (RhB) solution over WO 3 /g-C 3 N 4 composites were evaluated under visible light irradiation. The enhanced photocatalytic activity of WO 3 /g-C 3 N 4 composite could be attributed to the formation of the Z-scheme heterojunction system based on the active species trapping and hydroxyl radicals photoluminescence (PL) detection experiments. Furthermore, electrochemical impedance spectroscopy (EIS) and transient photocurrent measurements confirm the more efficient separation and transfer of photogenerated charge carriers on the WO 3 /g-C 3 N 4 composite than that of pure WO 3 or g-C 3 N 4 . This work would provide new insights into the design and preparation of face-to-face contact heterojunction photocatalysts for organic contaminant removal. [ABSTRACT FROM AUTHOR]

The MoS 2 /CdS composites with layered MoS 2 loaded on uniform CdS nanospheres were synthesized by a two-step process combination hydrothermal and solvothermal treatments, and then applied in photocatalytic hydrogen evolution under visible light irradiation. The as-prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectrometer (EDS), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Raman spectra, UV–vis diffuse reflectance absorption spectra (UV-DRS), nitrogen adsorption-desorption measurement, photoluminescence spectra (PL) and photoelectrochemical tests. The effects of loading contents of MoS 2 in the composites on the photocatalytic H 2 evolution activity were comparatively investigated with 0.45 mol L −1 Na 2 S and 0.55 mol L −1 Na 2 SO 3 as sacrificial agents. The results showed that the 5 wt% MoS 2 /CdS composite could achieve the highest photocatalytic H 2 evolution rate of 372 μmol h −1 and apparent quantum efficiency (AQE) about 7.31% under 420 nm monochromatic light irradiation. The remarkably enhanced photocatalytic activity of MoS 2 /CdS composite could be attributed to the effective transfer and separation of photogenerated charge carriers, and MoS 2 being as a cocatalyst to facilitating photocatalytic H 2 evolution reaction. A tentative mechanism of MoS 2 /CdS composites as photocatalysts for H 2 evolution was proposed. [ABSTRACT FROM AUTHOR]

In order to achieve a better trade-off among ionic conductivity, mechanical strength and chemical stability, a series of novel aggregated and ionic cross-linked anion exchange membranes (AEMs) are recommended, namely, ac S 6 QAPSF, ac S 8 QAPSF and ac S 10 QAPSF. Cross-linked network shoulders the responsibility to toughen the ac S x QAPSF. Appropriate micro-morphology is responsible for facilitating the conduction of OH− and improving the alkaline stability of the ac S x QAPSF. Compared with the original QAPSF, ac S x QAPSF membranes exhibit much better properties. Specifically, for ac S 8 QAPSF, a high OH− conductivity of 90.5 mS cm−1 is achieved at 80 °C, with the swelling degree of 10.0%. The tensile strength and elongation at break of wet ac S 8 QAPSF at 25 °C are 23.9 Mpa and 21.1%, respectively. After testing in 1 M NaOH at 80 °C for 30 days, the weight loss of ac S 8 QAPSF is 8.0%, with the losses of tensile strength and elongation at break of 13.8% and 13.3%, respectively. Its IEC and IC retentions are 92.0% and 90.5%, respectively. For ac S 8 QAPSF, a fuel cell peak power density of 0.612 W cm−2 is obtained at 60 °C. While for QAPSF, its fuel cell peak power density is only 0.101 W cm−2, and the film is cracked after the 30 days stability test. The unique ac S x QAPSF membrane can alleviate the tradeoff among ionic conductivity, mechanical strength and chemical stability. Image 1 • Novel aggregated and ionic cross-linked AEMs based on PSF are synthesized. • An important insight into the design of AEMs with high performance is provided. • The fuel cell of ac S 8 QAPSF achieved a peak power density of 612 mW cm−2 at 60 °C. [ABSTRACT FROM AUTHOR]

A series of cross-linked AEMs (c-DQPPO/PVA) are synthesized by using rigid polyphenylene oxide and flexible poly(vinyl alcohol) as the backbones. Dual cations are grafted on the PPO backbone to improve the ion exchange capacity (IEC), while glutaraldehyde is introduced to enhance compatibility and reduce swelling ratio of AEMs. In addition to the enhanced mechanical properties resulting from the rigid-flexible cross-linked network, c-DQPPO/PVA AEMs also exhibit impressive ionic conductivity, which can be attributed to their high IEC, good hydrophilicity of PVA, and well-defined micro-morphology. Additionally, due to confined dimension behavior and ordered micro-morphology, c-DQPPO/PVA AEMs demonstrate excellent chemical stability. Specifically, c-DQPPO/PVA-7.5 exhibits a wet-state tensile strength of 12.5 MPa and an elongation at break of 53.0 % at 25 °C. Its OH - conductivity and swelling degree at 80 °C are measured to be 125.7 mS cm -1 and 8.2 %, respectively, with an IEC of 3.05 mmol g -1 . After 30 days in a 1 M NaOH solution at 80 °C, c-DQPPO/PVA-7.5 experiences degradation rates of 12.8 % for tensile strength, 27.4 % for elongation at break, 14.7 % for IEC, and 19.2 % for ion conductivity. With its excellent properties, c-DQPPO/PVA-7.5 exhibits a peak power density of 0.751 W cm -2 at 60 °C in an H 2 -O 2 fuel cell., (© 2023 Wiley-VCH GmbH.)

The food hygiene problems caused by bacterial biofilms in food processing equipment are directly related to human life safety and health. Therefore, it is of great strategic significance to study new food sterilization technology. An acidic electrolyzed water (AEW) disinfectant is an electrochemical sterilization technology which has the characteristics of wide adaptability, high efficiency, and environmental friendliness. However, since the sterilization efficiency of AEW for biofilms is not ideal, it is necessary to increase the available chlorine content (ACC) in AEW. A feasible method to increase the ACC is by increasing the chlorine evolution reaction (CER) selectivity of the electrode for AEW preparation. In this paper, the RuO 2 @TiO 2 electrode was prepared by thermal decomposition combined with high-vacuum magnetron sputtering. Compared with the oxygen evolution reaction (OER) activity of an ordinary RuO 2 electrode, the OER activity of the RuO 2 @TiO 2 electrode is significantly reduced. However, the CER activity of the RuO 2 @TiO 2 electrode is close to the OER activity of RuO 2 . The CER mechanism of the RuO 2 @TiO 2 electrode is the second electron transfer, and the OER mechanism is the formation and transformation of OH ads . The potential difference between the CER and OER of the RuO 2 @TiO 2 electrode is 174 mV, which is 65 mV higher than that of the RuO 2 electrode, so the selectivity of the CER of the RuO 2 @TiO 2 electrode is remarkably improved. During the preparation of AEW, the ACC obtained with the RuO 2 @TiO 2 electrode is 1.7 times that obtained with the RuO 2 electrode. In the sterilization experiments on Escherichia coli and Bacillus subtilis biofilms, the logarithmic killing values of AEW prepared the by RuO 2 @TiO 2 electrode are higher than those of AEW prepared by the RuO 2 electrode., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

A nano Ir x Mn (1- x ) O y hybrid electrode with a L1 2 -IrMn 3 phase was used as a bifunctional catalyst with ultra-low iridium loading for overall water electrolysis in an acid solution for the first time. The HER activity of the Ir x Mn (1- x ) O y hybrid electrode not only exceeded that of IrO 2 , but also exceeded that of Pt/C. The OER activity of the Ir x Mn (1- x ) O y hybrid electrode also exceeded that of IrO 2 .

Electrochemical water splitting technology is considered to be the most reliable method for converting renewable energy such as wind and solar energy into hydrogen. Here, a nanostructured RuO 2 /Co 3 O 4 -RuCo-EO electrode is designed via magnetron sputtering combined with electrochemical oxidation for the oxygen evolution reaction (OER) in an alkaline medium. The optimized RuO 2 /Co 3 O 4 -RuCo-EO electrode with a Ru loading of 0.064 mg cm -2 exhibits excellent electrocatalytic performance with a low overpotential of 220 mV at the current density of 10 mA cm -2 and a low Tafel slope of 59.9 mV dec -1 for the OER. Compared with RuO 2 prepared by thermal decomposition, its overpotential is reduced by 82 mV. Meanwhile, compared with RuO 2 prepared by magnetron sputtering, the overpotential is also reduced by 74 mV. Furthermore, compared with the RuO 2 /Ru with core-shell structure ( η = 244 mV), the overpotential is still decreased by 24 mV. Therefore, the RuO 2 /Co 3 O 4 -RuCo-EO electrode has excellent OER activity. There are two reasons for the improvement of the OER activity. On the one hand, the core-shell structure is conducive to electron transport, and on the other hand, the addition of Co adjusts the electronic structure of Ru., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

An obvious H-UPD for a nano AuTiO2-x composite has been found for the first time in terms of the electrochemical characteristics of the Au composite. The electronic effect between Au and TiO2 and the oxygen vacancy defect would change the adsorption energy of H and HER activity. The HER activity of the AuTiO2-x electrode is 6.44 times that of the Au electrode.

The dependence on Pt catalysts has been a major issue of proton-exchange membrane (PEM) fuel cells. Strategies to maximize the Pt utilization in catalysts include two main approaches: to put Pt atoms only at the catalyst surface and to further enhance the surface-specific catalytic activity (SA) of Pt. Thus far there has been no practical design that combines these two features into one single catalyst. Here we report a combined computational and experimental study on the design and implementation of Pt-skin catalysts with significantly improved SA toward the oxygen reduction reaction (ORR). Through screening, using density functional theory (DFT) calculations, a Pt-skin structure on AuCu(111) substrate, consisting of 1.5 monolayers of Pt, is found to have an appropriately weakened oxygen affinity, in comparison to that on Pt(111), which would be ideal for ORR catalysis. Such a structure is then realized by substituting the Cu atoms in three surface layers of AuCu intermetallic nanoparticles (AuCu iNPs) with Pt. The resulting Pt-skinned catalyst (denoted as Pt(S)AuCu iNPs) has been characterized in depth using synchrotron XRD, XPS, HRTEM, and HAADF-STEM/EDX, such that the Pt-skin structure is unambiguously identified. The thickness of the Pt skin was determined to be less than two atomic layers. Finally the catalytic activity of Pt(S)AuCu iNPs toward the ORR was measured via rotating disk electrode (RDE) voltammetry through which it was established that the SA was more than 2 times that of a commercial Pt/C catalyst. Taking into account the ultralow Pt loading in Pt(S)AuCu iNPs, the mass-specific catalytic activity (MA) was determined to be 0.56 A/mg(Pt)@0.9 V, a value that is well beyond the DOE 2017 target for ORR catalysts (0.44 A/mg(Pt)@0.9 V). These findings provide a strategic design and a realizable approach to high-performance and Pt-efficient catalysts for fuel cells.