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Alkaline anion‐exchange membrane water electrolyzers (AEMWEs) for green hydrogen production have received intensive attention due to their feasibility of using earth‐abundant platinum group metal (PGM)‐free catalysts. Herein, the third metal is incorporated into NiFe‐based catalysts to regulate their electronic structures and morphologies, aiming to achieve sufficient oxygen evolution reaction (OER) activity and performance in AEMWEs. The ternary NiFeM (M: Cu, Co, or Mn) catalysts are featured with multiple layered structures and nanofoam network morphologies, consisting of highly OER‐active amorphous Ni‐rich oxide shells and electrically conductive metallic alloy cores. The physical and electronic perturbations to the NiFe induced by a third element lead to a fine‐tuning of the redox ability of the metal sites at the reaction centers, which breaks the scaling relationship between OH* and O* intermediates at the reaction centers. Thus, the unique structural configuration and electronic regulation simultaneously benefit catalytic activity and performance improvements. These NiFeM nanofoam catalysts demonstrated promising anode performance in actual AEMWEs, comparable to the IrO2 reference, especially at high current densities. Notably, using various electrolytes (e.g., KOH solution or pure water) for AEMWEs exhibited a different performance trend among studied NiFeM catalysts, likely due to dynamic changes of catalysts under various OER environments. [ABSTRACT FROM AUTHOR]

The more sluggish kinetics of hydrogen evolution catalysts in base as compare to that in acid to some degree restricts hydrogen production performance of hydroxide exchange membrane electrolyzers, especially when using earth‐abundant catalysts. Here a ternary nickel–copper–molybdenum hydrogen evolution catalyst is reported that exhibits ≈5 times higher turnover frequency than without copper doping. The X‐ray absorption near‐edge structure and valence band spectrum demonstrate that the light doping of copper into nickel–molybdenum alloy modulates the electronic structure and downshifts the d‐band center, resulting in accelerated hydrogen desorption, as consolidated by H2 temperature programmed desorption and theoretical calculation. An electrolyzer employing this cathode catalyst and a nickel–iron anode, gives a current density of 1.7 A cm−2 at 2.0 V with a pure‐water feed through the anode, which outperforms the 2025 target proposed by the United States Department of Energy, and even is operated continuously for over 1000 h with a decay rate of as low as 0.5 mV h−1. Post‐mortem analysis discloses that hydroxide exchange ionomer migration is one of the key factors affecting long‐term durability. This work demonstrates the feasibility of a low‐cost, water‐fed hydroxide exchange membrane electrolyzer achieving industrial‐level performance and lifetime. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are proposed as promising candidates for engineering advanced molecular sieving membranes due to their precise pore sizes, modifiable pore environment, and superior stability. However, COFs are insoluble in common solvents and do not melt at high temperatures, which presents a great challenge for the fabrication of COF‐based membranes (COFMs). Herein, for the first time, a new synthetic strategy is reported to prepare continuous and intact self‐standing COFMs, including 2D N‐COF membrane and 3D COF‐300 membrane. Both COFMs show excellent selectivity of H2/CO2 mixed gas (13.8 for N‐COF membrane and 11 for COF‐300 membrane), and especially ultrahigh H2 permeance (4319 GPU for N‐COF membrane and 5160 GPU for COF‐300 membrane), which is superior to those of COFMs reported so far. It should be noted that the overall separation performance of self‐standing COFMs exceeds the Robeson upper bound. Furthermore, a theoretical study based on Grand Canonical Monte Carlo (GCMC) simulation is performed to explain the excellent separation of H2/CO2 through COFMs. Thus, this facile preparation method will provide a broad prospect for the development of self‐standing COFMs with highly efficient H2 purification. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Three‐dimensional (3D) covalent organic frameworks (COFs) are crystalline porous polymers with potential in numerous high‐tech applications, but the linkages involved in their synthesis are still rather limited. Herein, we report novel 3D sp2 carbon‐linked COFs fabricated by the formation reaction of C=C bonds and their application in fluorescence imaging. These new COFs, namely JUC‐580 and JUC‐581, show high stability and excellent light‐emitting properties in solid state and dispersed in various solvents. Furthermore, we investigate the potential application of JUC‐581 as a drug carrier combined with fluorescence imaging. These results indicate that 3D sp2 carbon‐linked COFs are not only potential drug‐loaded and sustained release materials but also promising cell fluorescent stains. This study thus expands the structural categories of 3D COFs based on different linkages, and promotes their prospective applications for biomedicine and fluorescent materials. [ABSTRACT FROM AUTHOR]

The development of novel zeolite‐like materials with large channel windows and high stability is of importance but remains a tremendous challenge. Herein, we report the first example of a 3D covalent organic framework with zeolitic network, namely the zeolitic organic framework (ZOF). By combining two kinds of tetrahedral building blocks with fixed or relatively free bond angles, ZOF‐1 with the zeolitic crb net has been successfully synthesized. Its structure was determined by the single‐crystal 3D electron diffraction technique. Remarkably, ZOF‐1 shows high chemical stability, large pore size (up to 16 Å), and excellent specific surface area (≈2785 m2 g−1), which is superior to its analogues with the same network, including traditional aluminosilicate zeolites and zeolitic imidazole frameworks. This study thus opens a new avenue to construct zeolite‐like materials with pure organic frameworks and will promote their potential applications in adsorption and catalysis for macromolecules. [ABSTRACT FROM AUTHOR]

The development of bioinspired nano/subnano‐sized (<2 nm) ion channels is still considered a great challenge due to the difficulty in precisely controlling pore's internal structure and chemistry. Herein, for the first time, we report that three‐dimensional functionalized covalent organic frameworks (COFs) can act as an effective nanofluidic platform for intelligent modulation of the ion transport. By strategic attachment of 12‐crown‐4 groups to the monomers as ion‐driver door locks, we demonstrate that gating effects of functionalized COFs can be activated by lithium ions. The obtained materials exhibit an outstanding selective ion transmission performance with a high gating ratio (up to 23.6 for JUC‐590), which is among the highest values in metal ion‐activated solid‐state nanochannels reported so far. Furthermore, JUC‐590 offers high tunability, selectivity, and recyclability of ion transport proved by the experimental and simulated studies. [ABSTRACT FROM AUTHOR]

Owing to the finite building blocks and difficulty in structural identification, it remains a tremendous challenge to elaborately design and synthesize three‐dimensional covalent organic frameworks (3D COFs) with predetermined topologies. Herein, we report the first two cases of 3D COFs with the non‐interpenetrated hea net, termed JUC‐596 and JUC‐597, by using the combination of tetrahedral and triangular prism building units. Due to the presence of triptycene functional groups and fluorine atoms, JUC‐596 exhibits an exceptional performance in the H2 adsorption up to 305 cm3 g−1 (or 2.72 wt%) at 77 K and 1 bar, which is higher than previous benchmarks from porous organic materials reported so far. Furthermore, the strong interaction between H2 and COF materials is verified through the DFT theoretical calculations. This work represents a captivating example of rational design of functional COFs based on a reticular chemistry guide and demonstrates its promising application in clean energy storage. [ABSTRACT FROM AUTHOR]

With excellent designability, large accessible inner surface, and high chemical stability, covalent organic frameworks (COFs) are promising candidates as metal‐free heterogeneous catalysts. Here, we report two 3D radical‐based COFs (JUC‐565 and JUC‐566) in which radical moieties (TEMPO) are uniformly decorated on the channel walls via a bottom‐up approach. Based on grafted functional groups and suitable regular channels, these materials open up the application of COFs as highly efficient and selective metal‐free redox catalysts in aerobic oxidation of alcohols to relevant aldehydes or ketones with outstanding turn over frequency (TOF) up to 132 h−1, which has exceeded other TEMPO‐modified catalytic materials tested under similar conditions. These stable COF‐based catalysts could be easily recovered and reused for multiple runs. This study promotes potential applications of 3D functional COFs anchored with stable radicals in organic synthesis and material science. [ABSTRACT FROM AUTHOR]

Diabetic nephropathy (DN) is acknowledged as a serious chronic complication of diabetes mellitus. Nevertheless, its pathogenesis is complicated and unclear. Thus, in this study, the role of miR‐27a‐3p‐prohibitin/TMBIM6 signaling axis in the progression of DN was elucidated. Type 2 diabetic db/db mice and high glucose (HG)‐challenged HK‐2 cells were used as in vivo and in vitro models. Our results showed that miR‐27a‐3p was upregulated and prohibitin or transmembrane BAX inhibitor motif containing 6 (TMBIM6) was downregulated in the kidney tissues of db/db mice and HG‐treated HK‐2 cells. Silencing miR‐27a‐3p enhanced the expression of prohibitin and TMBIM6 in the kidney tissues and HK‐2 cells. Inhibition of miR‐27a‐3p improved functional injury, as evidenced by decreased blood glucose, urinary albumin, serum creatinine, and blood urea nitrogen levels. MiR‐27a‐3p silencing ameliorated renal fibrosis, reflected by reduced profibrogenic genes (e.g., transforming growth factor β1, fibronectin, collagen I and III, and α‐smooth muscle actin). Furthermore, inhibition of miR‐27a‐3p relieved mitochondrial dysfunction in the kidney of db/db mice, including upregulation of mitochondrial membrane potential, complex I and III activities, adenosine triphosphate, and mitochondrial cytochrome C, as well as suppressing reactive oxygen species production. In addition, miR‐27a‐3p silencing attenuated endoplasmic reticulum (ER) stress, reflected by reduced expression of p‐IRE1α, p‐eIF2α, XBP1s, and CHOP. Mechanically, we identified prohibitin and TMBIM6 as direct targets of miR‐27a‐3p. Inhibition of miR‐27a‐3p protected HG‐treated HK‐2 cells from apoptosis, extracellular matrix accumulation, mitochondrial dysfunction, and ER stress by regulating prohibitin or TMBIM6. Taken together, we reveal that miR‐27a‐3p‐prohibitin/TMBIM6 signaling axis regulates the progression of DN, which can be a potential therapeutic target. [ABSTRACT FROM AUTHOR]

The development of three‐dimensional (3D) covalent organic frameworks (COFs) with high chemical stability is of critical importance for their practical use. In this work, it is demonstrated that the stability of 3D COFs can be improved by periodic decoration of isopropyl groups on their backbones. Owing to the strong hydrophobicity of the alkyl groups, the resultant COFs show high crystallinity, permanent pores, and exceptional stability in harsh environments, such as strong acids (3 m HCl or 3 m H2SO4 for one week), a strong base (20 m NaOH for one week), and boiling water (100 °C for one month). Furthermore, these highly stable and hydrophobic COFs display excellent oil/water separation performance with >99 % separation efficiency over a wide pH range. This work demonstrates the use of alkyl decoration in 3D COFs to tune their chemical stability and expand their potential applications. [ABSTRACT FROM AUTHOR]

Understanding the pH dependent shift of the oxidation peak of the underpotential deposited hydrogen (Hupd) in cyclic voltammograms on the Pt surface is of significance in terms of both the fundamentals of electrochemistry and the rational design of catalysts for the hydrogen oxidation/evolution reactions (HOR/HER). In this work, we provide compelling evidence that the pH dependent shift in the Hupd peak on Pt surfaces is driven by the structure of interfacial water rather than the specific adsorption of cations on the electrode surface. Combined cyclic voltammetric and surface enhanced spectroscopic investigations using an organic cation and crown‐ether chelated alkali metal cations show that specific adsorption of metal and organic cations on the Pt surface at the conditions relevant to the HOR/HER is unlikely. The vibrational band corresponding to strongly bound water is monitored when the electrode potential is varied in the Hupd range in both acid and base. [ABSTRACT FROM AUTHOR]

Despite recent intense interest in the development of catalysts for the electrochemical nitrogen reduction reaction (ENRR), mechanistic understanding and catalyst design principles remain lacking. In this work, we develop a strategy to determine the density of initial and steady‐state active sites on ENRR catalysts that follow the Mars–van Krevelen mechanism via quantitative isotope‐exchange experiments. This method allows the comparison of intrinsic activities of active sites and facilitates the identification and improvement of active‐site structures for ENRR. Combined with detailed density functional theory calculations, we show that the rate‐limiting step in the ENRR is likely the initial N≡N bond activation via the addition of a proton and an electron to the adsorbed N2 on the N vacancies to form N2H. The methodology developed and mechanistic insights gained in this work could guide the rational catalyst design in the ENRR. [ABSTRACT FROM AUTHOR]

Papillary thyroid carcinoma is one of the most fatal malignant endocrine tumors, and the prognosis remains poor because of the lack of effective therapeutic targets. In this study, we demonstrated that the level of miR‐199b‐5p was markedly downregulated in papillary thyroid carcinoma. The ectopic expression level of miR‐199b‐5p in papillary thyroid carcinoma cell B‐CPAP could inhibit growth, migration, and invasion as well as epithelial‐mesenchymal transition (EMT) and decreased cell metastasis in vivo, but silencing miR‐199b‐5p caused a contradictory outcome. Additionally, Stonin 2 (STON2) was identified as a direct target gene of miR‐199b‐5p. Consistent with the downregulation of miR‐199b‐5p, the overexpression of STON2 induced the growth, migration and invasion of B‐CPAP cells. It was also demonstrated that miR‐199b‐5p suppressed papillary thyroid carcinoma cell aggressiveness by targeting STON2. Furthermore, the overexpression of miR‐199b‐5p inhibited cell proliferation, promoted apoptosis, and increased the chemo‐sensitivity of thyroid carcinoma B‐CPAP cells toward the chemotherapy drug paclitaxel. Finally, in vivo experiments further demonstrated that miR‐199b‐5p suppressed tumor growth in nude mice. Thus, this study revealed that miR‐199b‐5p functions as antioncogene miRNA in papillary thyroid carcinoma cells and that the miR‐199b‐5p/STON2 axis might be a potential treatment option for papillary thyroid carcinoma. © 2018 IUBMB Life, 71(1):28–40, 2019 [ABSTRACT FROM AUTHOR]

Abstract: Chemical functionalization of covalent organic frameworks (COFs) is critical for tuning their properties and broadening their potential applications. However, the introduction of functional groups, especially to three‐dimensional (3D) COFs, still remains largely unexplored. Reported here is a general strategy for generating a 3D carboxy‐functionalized COF through postsynthetic modification of a hydroxy‐functionalized COF, and for the first time exploration of the 3D carboxy‐functionalized COF in the selective extraction of lanthanide ions. The obtained COF shows high crystallinity, good chemical stability, and large specific surface area. Furthermore, the carboxy‐functionalized COF displays high metal loading capacities together with excellent adsorption selectivity for Nd3+ over Sr2+ and Fe3+ as confirmed by the Langmuir adsorption isotherms and ideal adsorbed solution theory (IAST) calculations. This study not only provides a strategy for versatile functionalization of 3D COFs, but also opens a way to their use in environmentally related applications. [ABSTRACT FROM AUTHOR]

Gaseous HCl as a by-product is often produced from chlorination processes using Cl2 gas. Onsite Cl2 regeneration from HCl is highly desirable as it eliminates the need to buy new Cl2 and dispose HCl waste. A gaseous HCl electrolysis with Fe3+/Fe2+ redox-mediated cathode is demonstrated for Cl2 regeneration. HCl is oxidized to generate Cl2 and protons in the anode while Fe3+ is reduced to Fe2+ in the cathode. Simultaneously Fe3+ is regenerated by chemical oxidation of Fe2+ by oxygen (air) that also produces water. A low operational voltage and high coulombic efficiency are achieved by using a novel composite porous membrane and hydrophobic anode. Specifically, a cell voltage of only 0.64 V is needed at the typical current density of 4 kA m−2, leading to a low energy consumption of 483 kWh per ton of Cl2 (124 kJ mol [ABSTRACT FROM AUTHOR]

Ene-functionalized ionic liquids with a range of different cationic groups and counteranions react stoichiometrically within a tetrathiol-divinyl ether formulation within 20 minutes to form thiol-ene polymers with measurable ionic conductivities via a photoinitiated polymerization and crosslinking reaction. Dynamic mechanical analysis indicates that these networks are more spatially heterogeneous and possess higher glass transition temperatures ( Tg) compared with thiol-ene formulations without charge. While tuning the molar content of ionic liquid monomer is one method for adjusting the crosslink and charge densities of the thiol-ene polymeric ionic liquid networks, the presence of cation-anion interactions also plays a critical role in dictating the thermomechanical and conductive properties. Particularly, while cationic structure effects are not significant on the polymer properties, the use of a weakly coordinating hydrophobic anion (bistriflimide) instead of bromide-based networks results in an apparent decrease in hydrated ion conductivity (7.4 to 1.5 mS cm−1) and Tg (−9.6 to −17.8 °C). [ABSTRACT FROM AUTHOR]

The emerging fiber-shaped supercapacitors (FSSs) have motivated tremendous research interest in energy storage devices. However, challenges still exist in the pursuit of combination of excellent electrochemical performance and mechanical stretchability. Here, a core-sheath asymmetric FSS is first made by wrapping gel electrolyte coated carbon nanotube (CNT)@MnO2 core fiber with CNT@PPy composite film. Then a stretchable helical structure is formed by over-twisting the FSS. The resulted stretchable asymmetric FSS exhibits a specific capacitance of 60.435 mF cm−2 at the scan rate of 10 mV s−1 and the capacitance performance is well maintained during repeated stretching to 20% strain. Furthermore, a high energy density of 18.88 μW h cm−2 is achieved for the stretchable FSS due to its high specific capacitance and extended potential window of 1.5 V. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting to generate molecular hydrogen requires catalysts that are cheap, active, and stable, particularly for alkaline electrolyzers, where the cathodic hydrogen evolution reaction is slower in base than in acid even on platinum. Herein, we describe the synthesis of new hollow Chevrel-phase NiMo3S4 and its alkaline hydrogen evolution reaction (HER) performance: onset potential of −59 mV, Tafel slope of 98 mV per decade, and exchange current density of 3.9×10−2 mA cm−2. This Chevrel-phase chalcogenide also demonstrates outstanding long-term stability under harsh HER cycling conditions. Chevrel-phase nanomaterials show promise as efficient, low-cost catalysts for alkaline electrolyzers. [ABSTRACT FROM AUTHOR]

Highly alkali-stable cationic groups are a critical component of hydroxide exchange membranes (HEMs). To search for such cations, we studied the degradation kinetics and mechanisms of a series of quaternary phosphonium (QP) cations. Benzyl tris(2,4,6-trimethoxyphenyl)phosphonium [BTPP-(2,4,6-MeO)] was determined to have higher alkaline stability than the benchmark cation, benzyl trimethylammonium (BTMA). A multi-step methoxy-triggered degradation mechanism for BTPP-(2,4,6-MeO) was proposed and verified. By replacing methoxy substituents with methyl groups, a superior QP cation, methyl tris(2,4,6-trimethylphenyl)phosphonium [MTPP-(2,4,6-Me)] was developed. MTPP-(2,4,6-Me) is one of the most stable cations reported to date, with <20 % degradation after 5000 h at 80 °C in a 1 m KOD in CD3OD/D2O (5:1 v/ v) solution. [ABSTRACT FROM AUTHOR]

A series of poly(2,4-dimethyl-1,4-phenylene oxide) hydroxide-exchange membranes (HEMs) with cation strings containing a well-defined number of cations (CS-n) and similar, high ion-exchange capacities are synthesized to investigate the effect of cation distribution on key HEM properties. As the number of cations on each string grows, the size of the ionic clusters increases from 10 to 55 nm. Well-connected ion pathways and a hydrophobic framework are observed for n≥4. The enhanced phase segregation increases the hydroxide conductivity from CS-1 to CS-6 (30 to 65 mScm-1) and suppresses the water uptake (from 143% to 62%). Moreover, molar hydroxide conductivities for CS-n membranes show two distinctive stages as n increases: ~23 Scm2mol-1 for n≤3; and ~34 cm2mol-1 for n≥4. [ABSTRACT FROM AUTHOR]

A monolithic nanoporous silver catalyst is developed to achieve a better performance than platinum at very low overpotentials for oxygen reduction reaction in alkaline conditions. Benefiting from the reaction‐promoting electrode architecture and the enhanced surface area, such a nanoporous silver catalyst exhibits a threefold improved overall activity compared to that of commercial state‐of‐the‐art platinum carbon catalysts at 0.90 V versus RHE. [ABSTRACT FROM AUTHOR]

Palladium (PdNTs) and gold nanotubes (AuNTs) were synthesized by the galvanic displacement of silver nanowires. PdNTs and AuNTs have wall thicknesses of 6 nm, outer diameters of 60 nm, and lengths of 5-10 and 5-20 μm, respectively. Rotating disk electrode experiments showed that the PdNTs and AuNTs have higher area normalized activities for the oxygen reduction reaction (ORR) than conventional nanoparticle catalysts. The PdNTs produced an ORR area activity that was 3.4, 2.2, and 3.7 times greater than that on carbon-supported palladium nanoparticles (Pd/C), bulk polycrystalline palladium, and carbon-supported platinum nanoparticles (Pt/C), respectively. The AuNTs produced an ORR area activity that was 2.3, 9.0, and 2.0 times greater than that on carbon-supported gold nanoparticles (Au/C), bulk polycrystalline gold, and Pt/C, respectively. The PdNTs also had lower onset potentials than Pd/C and Pt/C for the oxidation of methanol (0.236 V), ethanol (0.215 V), and ethylene glycol (0.251 V). In comparison to Pt/C, the PdNTs and AuNTs further demonstrated improved alcohol tolerance during the ORR. [ABSTRACT FROM AUTHOR]

The design and synthesis of 3D covalent organic frameworks (COFs) have been considered a challenge, and the demonstrated applications of 3D COFs have so far been limited to gas adsorption. Herein we describe the design and synthesis of two new 3D microporous base-functionalized COFs, termed BF-COF-1 and BF-COF-2, by the use of a tetrahedral alkyl amine, 1,3,5,7-tetraaminoadamantane (TAA), combined with 1,3,5-triformylbenzene (TFB) or triformylphloroglucinol (TFP). As catalysts, both BF-COFs showed remarkable conversion (96 % for BF-COF-1 and 98 % for BF-COF-2), high size selectivity, and good recyclability in base-catalyzed Knoevenagel condensation reactions. This study suggests that porous functionalized 3D COFs could be a promising new class of shape-selective catalysts. [ABSTRACT FROM AUTHOR]

Stable and able: The hydroxide‐conducting cationic functional group used in the hydroxide‐exchange membranes of fuel cells is key to controlling chemical stability and solubility. A new imidazolium cation, 1,4,5‐trimethyl‐2‐(2,4,6‐trimethoxyphenyl)imidazolium, is designed to take advantage of both strong electron‐donation properties and steric hindrance. Synergy between these two effects leads to an efficient hydroxide‐exchange membrane, with increased alkaline stability and improved OH− conductivity. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNWs) and nanoparticles (AgNPs) have been synthesized to facilitate hydroxide-exchange membrane fuel cell development and commercialization. AgNWs and AgNPs with variable diameters (25-60 nm AgNWs, 2.4-30 nm AgNPs) have been studied with rotating-disk electrode experiments to examine the impact of size and morphology on the oxygen reduction reaction (ORR). Although a detrimental particle size effect is observed, AgNWs exceed the specific activity of bulk polycrystalline Ag. AgNWs with a diameter of 25 nm further exceed the ORR specific and mass activity of 2.4 nm AgNPs 5.3 times and by 16 %, respectively. Rotating ring-disk electrode testing demonstrates minimal peroxide formation on AgNWs; peroxide production increases with the use of AgNPs by as much as an order of magnitude and further increases with particle size reduction. Silver catalysts demonstrate alcohol tolerance for ORR, illustrating the benefit of silver and AgNWs as catalysts in hydroxide and alcohol hydroxide-based fuel cells. [ABSTRACT FROM AUTHOR]

This article discusses findings of a study which examined the wetting diameter and lifetime of a water droplet on the surface of a bare, ZSM-5 coated and Zeolite-A coated stainless steel 304 substrate at different initial surface temperatures. Thin films are designed to reduce the pressure drop of the air that have been forced through the system, decreases the operation noise and the pumping cost. Metal corrosion is one factor to consider for a heat exchanger and several coatings are available as corrosion protection, including galvanized coatings and plasma vapor deposition (PVD) coatings.

Hydroxide-exchange membranes are developed for facilitated transport CO2 in post-combustion flue-gas feed. First, a correlation between the basicity of fixed-site functional groups and CO2-separation performance is discovered. This relationship is used to identify phosphonium as a promising candidate to achieve high CO2-separation performance. Consequently, quaternary phosphonium-based hydroxide-exchange membranes are demonstrated to have a separation performance that is above the Robeson upper bound. Specifically, a CO2 permeability as high as 1090 Barrer and a CO2/N2 selectivity as high as 275 is achieved. The high performance observed in the membranes can be attributed to the quaternary phosphonium moiety. [ABSTRACT FROM AUTHOR]

Innenrücktitelbild: Understanding the pH Dependence of Underpotential Deposited Hydrogen on Platinum (Angew. B Oberflächenverstärkte Infrarotspektren b zeigen, dass Grenzflächen-Kationen mit Elektrodenoberflächen interagieren, indem sie die Struktur des Wassers an der Grenzfläche verändern, und nicht ihre spezifische Adsorption. In ihrem Forschungsartikel auf S. 17882 demonstrieren Y. Yan, B. Xu et al., dass die Modifizierung der Struktur von Grenzflächenwasser den Schlüssel zur Verbesserung der Kinetik von Wasserstoffoxidation und -entwicklung darstellen könnte. [Extracted from the article]

Titelbild: Quantification of Active Sites and Elucidation of the Reaction Mechanism of the Electrochemical Nitrogen Reduction Reaction on Vanadium Nitride (Angew. In ihrer Zuschrift auf S. 13906 bestimmen Y. Yan, J. G. Chen, B. Xu und Mitarbeiter mithilfe von SP 14 sp N/ SP 15 sp N-Isotopenaustausch die Dichte der initialen und stationären aktiven Zentren bei der elektrochemischen Stickstoffreduktion auf Vanadiumoxynitrid. In ihrer Zuschrift auf S. 13906 bestimmen Y. Yan, J. G. Chen, B. Xu und Mitarbeiter mithilfe von SP 14 sp N/ SP 15 sp N-Isotopenaustausch die Dichte der initialen und stationären aktiven Zentren bei der elektrochemischen Stickstoffreduktion auf Vanadiumoxynitrid. [Extracted from the article]