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Developing new materials for Li‐ion and Na‐ion batteries is a high priority in materials science. Such development always includes performance tests and scientific research. Synchrotron radiation techniques provide unique abilities to study batteries. Electrochemical cell design should be optimized for synchrotron studies without losing electrochemical performance. Such design should also be compatible with operando measurement, which is the most appropriate approach to study batteries and provides the most reliable results. The more experimental setups a cell can be adjusted for, the easier and faster the experiments are to carry out and the more reliable the results will be. This requires optimization of window materials and sizes, cell topology, pressure distribution on electrodes etc. to reach a higher efficiency of measurement without losing stability and reproducibility in electrochemical cycling. Here, we present a cell design optimized for nuclear resonance techniques, tested using nuclear forward scattering, synchrotron Mössbauer source and nuclear inelastic scattering. [ABSTRACT FROM AUTHOR]

High‐entropy materials (HEMs) represent a revolutionary class of materials that have garnered significant attention in the field of materials science due to their extraordinary properties in diverse fields of applications such as catalysis and electrochemistry. The past decade has witnessed a substantial increase in the study of these materials, exploring new synthesis routes and compositions. What began as the synthesis of high‐entropy alloys has expanded to encompass several classes of HEMs such as oxides, hydroxides, sulfides, nitrides, and carbides, among others. Several synthesis methods have been developed to produce these materials. This review therefore highlights the fundamental concepts of HEMs, including their core effects, with a major emphasis on their scalable synthesis routes. The advantages and drawbacks of these methods are also discussed. As HEMs transition from the lab to large‐scale production, there is a growing need for cost‐effective and scalable synthesis methods with high material yield suitable for a variety of applications like hydrogen storage, catalysis, batteries, supercapacitors, and fuel cells. Hence, this review serves as an introduction to scalable synthesis routes based on crystal structure, desired elements, synthesis times, and equipment costs. [ABSTRACT FROM AUTHOR]

Electrochemiluminescence (ECL) is rapidly evolving from an analytical method into an optical microscopy. The orthogonality of the electrochemical trigger and the optical readout distinguishes it from classic microscopy and electrochemical techniques, owing to its near‐zero background, remarkable sensitivity, and absence of photobleaching and phototoxicity. In this minireview, we summarize the recent advances in ECL imaging technology, emphasizing original configurations which enable the imaging of biological entities and the improvement of the analytical properties by increasing the complexity and multiplexing of bioassays. Additionally, mapping the (electro)chemical reactivity in space provides valuable information on nanomaterials and facilitates deciphering ECL mechanisms for improving their performances in diagnostics and (electro)catalysis. Finally, we highlight the recent achievements in imaging at the ultimate limits of single molecules, single photons or single chemical reactions, and the current challenges to translate the ECL imaging advances to other fields such as material science, catalysis and biology. [ABSTRACT FROM AUTHOR]

Summary: Current solid- and liquid-state electrode materials with extreme physical states show inherent limitation in achieving the ultra-stable batteries. Herein, we present a colloidal electrode design with an intermediate physical state to integrate the advantages of both solid- and liquid-state materials. The colloidal electrode was designed based on the inherent water competition effect of (SO4)2− from the aqueous electrolyte and inherently water-soluble polyethylene glycol (PEG)/ZnI2 from the cathode. The constructed aqueous Zn||PEG/ZnI2 colloid battery demonstrated ultra-stable cycling performance with Coulombic efficiencies approaching 100% and a capacity retention of 86.7% over 10,700 cycles, without requiring anodic modification. In addition, the battery also exhibits compatibility with multiple operating conditions including fluctuating charging, limited self-discharging rate, different charging statuses, and fast charging. Moreover, the battery also shows practical potential by integrating with a photovoltaic solar panel charging. This design provides a broad platform for building the next-generation aqueous batteries with ultra-long lifetime.

Summary: A crucial challenge in hydrogen production through electrolysis is developing inexpensive, earth-abundant, and highly efficient Pt-free electrocatalysts for the hydrogen evolution reaction (HER). Molybdenum carbide is ideal for this application because of its special electrical structure, low cost, and advantageous characteristics. Herein, the long-lived electrocatalysts for HER have been synthesized via the direct current (DC) arc discharge plasma method under ambient air conditions, and the relationship between the properties of materials and catalytic characteristics has been established. The samples differed in the ratio of molybdenum, graphite, and melamine. The sample with the highest proportion of melamine in the initial mixture has Mo2C-MoO2 heterointerfaces, which demonstrates the highest and most stable electrocatalytic activity with the overpotential of 148 mV at 10 mA·cm-2 and Tafel slope of 63 mV·dec−1 in alkaline electrolyte. Meanwhile, the electrodes demonstrated long-lived electrochemical durability for two weeks and investigated the features of forming a stable system for HER.

Centralized laboratories in which analytical processes are automated to enable the analysis of large numbers of samples at relatively low cost are used for analytical testing throughout the world. However, healthcare is changing, partly due to the general recognition that care needs to be more patient-centered and putting the patient at the center of action. One way to achieve this goal is to consider point-of-care testing (PoC) devices as alternative analytical concepts. This requires miniaturization of current analytical concepts and the use of cost-effective diagnostic tools with appropriate sensitivity and specificity. Electrochemical sensors are ideally adapted as they provide robust, low-cost, and miniaturized solutions for the detection of variable analytes, yet lack the high sensitivity comparable to more classical diagnosis approaches. Advances in nanotechnology have opened up a plethora of different nanomaterials to be applied as electrode and/or sensing materials in electrochemical biosensors. The choice of materials significantly influences the sensor's sensitivity, selectivity, and overall performance. A critical review of the state of the art with respect to the development of the utilized materials (between 2019 and 2023) and where the field is heading to are the focus of this article. [ABSTRACT FROM AUTHOR]

The paper presents the basic concepts and the peculiarities of teaching electrochemistry on the example of St. Petersburg University. We discuss the main courses in electrochemistry and the role of theory and laboratory practice in the education of BSc and MSc students in Chemistry or Materials Science, including those, who will specialize in electrochemistry. The tight integration of basic lecture courses with seminars and experimental laboratory works is considered as the key element of electrochemistry education. [ABSTRACT FROM AUTHOR]

Summary: Because of their unique layer structure, 2D materials have demonstrated to be promising electrode materials for rechargeable batteries. However, individual 2D materials cannot meet all the performance requirements of energy density, power density, and cycle life. Constructing 2D materials-based heterostructures offers an opportunity to synergistically handle the deficiencies of individual 2D materials and modulate the physical and electrochemical properties. The enlarged interlayer distance and increased binding energy with ions of heterostructures can facilitate charge transfer, boost electrochemical reactivities, resulting in an enhanced performance in rechargeable batteries. Here we summarize the latest development of heterostructures consisted of 2D materials and their applications in rechargeable batteries. Firstly, different preparation strategies and optimized structure engineering strategies of 2D materials-based heterostructures are systematically introduced. Secondly, the unique functions of 2D materials-based heterostructures in rechargeable batteries are discussed respectively. Finally, challenges and perspectives are presented to inspire the future study of 2D materials-based heterostructures.

Summary: The effect on catalytic behavior induced by different morphology of NiO supports has been investigated using the example of gold-catalyzed CO oxidation. Three NiO-supported nanogold consisting of nanogold deposited onto NiO nanorods (NiO-R), nanosheet (NiO-S), and nanodiscs (NiO-D) were prepared. Transmission electron microscopy(TEM)/Scanning transmission electron microscopy(STEM) investigations indicated that Au particles dominantly exposed Au(111) facets virtually independent of NiO architectures. Au/NiO-S displayed a normal Arrhenius-type behavior. Au/NiO-R and Au/NiO-D showed an atypical behavior, characterized by a U-shaped curve of activity vs. temperature, which is attributed to the carbonate accumulation on whose catalytically active sites. On Au/NiO-R, a stable CO-conversion rate of 1.78 molCO gAu−1 h−1 at 30°C was achieved, which is among the higher rates reported so far for supported Au-based systems. DRIFTS measurement identified Auδ+ species as crucial CO adsorption sites promoting CO oxidation, and the catalytic CO oxidation should obey Mars-van Krevelen (240°C).

Summary: The biosilicification of diatoms allows for the customization of the synthesis of functionalized diatom frustules. The S active sites (–SH) on diatom frustules were created by adding the organic silicon sources tetramethoxysilane (TMOS) and (3-mercaptopropyl)trimethoxysilane (MPTMS). The mechanisms of adsorption-reduction and the indirect effects of S active sites on electrochemical performance were declared. The DBS@C-Ag-3 anode material sourced from the cultivation condition with a silicon source of TMOS:MPTMS = 3:1 shows the best comprehensive performance and delivers a discharge capacity of ∼660 mAh·g−1 after 1000 cycles at 1 A·g−1. The electrochemical performance of DBS@C-Ag anode materials is also found to be dominated by structure at high temperatures and conductivity at low temperatures. Such a diatom frustule structure with sulfhydryl functionalization is promising for anode materials, and it suggests a biological strategy for creating other electrode materials by modifying them with metals to improve electrochemical performances.

In the 21st century, materials science has developed rapidly. Mesoporous carbon is now among the most attractive substances due to its enormous specific surface area, high porosity, and structured pore structure. There are many methods to synthesize mesoporous carbon, among which the template method is widely used because of the variety of templates and synthesis pathways. Mesoporous carbon has been used in many fields. Its good electrical conductivity, lightweight nature, and low price have led to many applications in electrochemistry, such as capacitors, electrodes, and materials for electric vehicles. This work contains a literature overview on the synthesis methods and modification techniques for mesoporous carbon, as well as its application in electrochemistry, which serves as a guide for the future growth of mesoporous carbon research. [ABSTRACT FROM AUTHOR]

Keywords: electrosynthesis; asymmetric synthesis; chirality; anodic oxidation; cathodic reduction; electrolysis; homogeneous catalysis; radicals EN electrosynthesis asymmetric synthesis chirality anodic oxidation cathodic reduction electrolysis homogeneous catalysis radicals 2926 2942 17 08/31/23 20230915 NES 230915 Graph 1 Introduction The present-day concerns with environmental protection are driving chemists more and more to find cleaner, step-economical and low-waste generating approaches to synthesis, which also use readily available starting materials and do not consume much energy. It was postulated that the benzylic radicals, obtained by single electron oxidation, underwent radical-radical coupling with a radical formed by a chiral catalyst bound-substrate in a manner similar to that of the previous example (Scheme 1). Key to success was the ability of the rhodium catalyst to reduce the oxidation potential of the catalyst-bound substrate in its enolate form B I b , after deprotonation, allowing a mild and selective anodic oxidation reaction to take place (Scheme 2). 2.3 Alkynylation [C(sp 3)-C(sp) Bond Formation] Although the Shono oxidation for the -functionalization of amines is one of the most studied anodic oxidation reactions, catalytic asymmetric variants of the reaction have not been very much explored. [Extracted from the article]

Keywords: electrochemistry; electrocatalysis; olefin metathesis; ruthenium catalysis EN electrochemistry electrocatalysis olefin metathesis ruthenium catalysis 1477 1481 5 07/11/23 20230725 NES 230725 Graph Olefin metathesis is one of the most valuable reactions in organic chemistry for the formation of C=C bonds, as reflected by its widespread application in synthetic chemistry, [1] materials science, [2] and polymer science. Electrochemistry, electrocatalysis, olefin metathesis, ruthenium catalysis. [Extracted from the article]

Due to their ability to form stable molecular complexes that have tailor‐made properties, terpyridine ligands are of great interest in chemistry and material science. In this regard, we prepared two terpyridine ligands with two different fluorinated phenyl rings on the backbone. The corresponding CoII and FeII complexes were synthesized and characterized by single‐crystal X‐ray structural analysis, electrochemistry and temperature‐dependent SQUID magnetometry. Single crystal X‐ray diffraction analyses at 100 K of these complexes revealed Co−N and Fe−N bond lengths that are typical of low spin CoII and FeII centers. The metal centers are coordinated in an octahedral fashion and the fluorinated phenyl rings on the backbone are twisted out of the plane of the terpyridine unit. The complexes were investigated with cyclic voltammetry and UV/Vis‐NIR spectroelectrochemistry. All complexes show a reversible oxidation and several reduction processes. Temperature dependent SQUID magnetometry revealed a gradual thermal SCO behavior in two of the complexes, while EPR spectroscopy provided further insights on the electronic structure of the metal complexes, as well as site of reduction. [ABSTRACT FROM AUTHOR]

Decyanation is an important process in the synthesis of aromatic molecules in the studies of pharmaceutical research, medical and materials sciences. In late‐stage modifications of privileged carbo/heterocyclic scaffolds, radical‐type decyanation techniques have been devised to date. As a result, the chemistry of cyano‐involved conversions, a hotly debated subject over the past few decades, has advanced significantly. The cyano group (CN), on the other hand, has rarely been acknowledged as a good reaction site due to its thermodynamic robustness. The most recent advancements in catalytic radical decyanation protocols that CN behaved as a leaving group has made are surveyed in this article. Following the introduction of a number of different reaction modes, the catalytic reactions that are used to activate the C−CN bonds are primarily categorized, and the text herein are divided into three groups: (1) photo‐catalyzed decyanation transformations, (2) electro‐catalyzed decyanation transformations, and (3) transition‐metal‐catalyzed or metal‐free decyanation transformations. With an emphasis on the catalytic systems and synthetic applications in C−CN bond activation, this review will provide the readers with an overview of decyanation chemistry in radical reactions. [ABSTRACT FROM AUTHOR]

The scientific school of Alexander Frumkin, a world-renowned electrochemist born in Chisinau, was at the origin of the electrochemical science in the Republic of Moldova. Research directions, such as high-rate anodic dissolution, plasma electrochemical treatment, electrical methods for mass transfer control, identified as "extreme electrochemistry", and the electrochemical nanostructuring, have been significantly developed at the national level from both fundamental and applicative viewpoints. Moreover, the European cooperation considerably broadened the opportunities for Moldovan electrochemists in the related areas such as materials science and surface engineering. The present review highlights the main scientific contributions of Moldovan researchers to the world information process related to the above mentioned domains and to the academic–industrial collaboration. [ABSTRACT FROM AUTHOR]

In the last few decades, the development and use of thin films and nanostructured materials to enhance physical and chemical properties of materials has been common practice in the field of materials science and engineering. The progress which has recently been made in tailoring the unique properties of thin films and nanostructured materials, such as a high surface area to volume ratio, surface charge, structure, anisotropic nature, and tunable functionalities, allow expanding the range of their possible applications from mechanical, structural, and protective coatings to electronics, energy storage systems, sensing, optoelectronics, catalysis, and biomedicine. Recent advances have also focused on the importance of electrochemistry in the fabrication and characterization of functional thin films and nanostructured materials, as well as various systems and devices based on these materials. Both cathodic and anodic processes are being extensively developed in order to elaborate new procedures and possibilities for the synthesis and characterization of thin films and nanostructured materials. [ABSTRACT FROM AUTHOR]

Nitrogen reduction reaction (NRR) is used to convert nitrogen (N2) to ammonia (NH3) at ambient conditions. In general, acidic electrolytes are used to provide protons (H+), however, this leads to low selectivity due to H2 formation via the hydrogen evolution reaction (HER). Recently, it is shown that Ti2N MXene is active and selective for NRR in acidic electrolyte, and operates through a Mars‐van Krevelen (MvK) mechanism. However, the effect of pH on its catalytic performance is not well understood. Here, experiments are performed in varying pH values and relations are developed between pH and performance. The findings of this study indicate that the lowest NRR onset occurs within pH 2 systems exhibiting a nonlinear trend. However, as pH decreases, overpotential decreases, and kinetics increase due to H+ participation. FE values are found to increase as pH increased. These findings will be extended to other materials to design optimal electrolytic systems for NRR. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Oxygen reduction reaction (ORR) is the pivotal portion in many electrochemical energy conversion and storage technologies. However, the complex mechanisms and sluggish kinetics of ORR have also become one of the key issues hindering the development and application of these technologies. Recently, single‐atom catalysts (SACs) with well‐defined atomic active centers and theoretical 100% atomic utilization have attracted broad interests in the area of electrocatalytic ORR. The electrocatalytic ORR performance of SACs is fundamentally determined by the intrinsic activity of the single‐atom active site and increasing the number of active sites involved in the ORR can further enhance the ORR activity of SACs. In this review, advances in atomically dispersed metal electrocatalysts for ORR in the last three years are summarized. Three main regulation strategies for achieving SACs with excellent intrinsic activity in the context of the ORR mechanism are involved including modulation of coordination environments, the construction of intrinsic defects, and the introduction of dual active sites. Moreover, discussions on improving the loading and utilization of active sites are given. Finally, the current challenges and opportunities for the development of SACs for ORR are presented. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Oxygen reduction reaction (ORR) is the pivotal portion in many electrochemical energy conversion and storage technologies. However, the complex mechanisms and sluggish kinetics of ORR have also become one of the key issues hindering the development and application of these technologies. Recently, single‐atom catalysts (SACs) with well‐defined atomic active centers and theoretical 100% atomic utilization have attracted broad interests in the area of electrocatalytic ORR. The electrocatalytic ORR performance of SACs is fundamentally determined by the intrinsic activity of the single‐atom active site and increasing the number of active sites involved in the ORR can further enhance the ORR activity of SACs. In this review, advances in atomically dispersed metal electrocatalysts for ORR in the last three years are summarized. Three main regulation strategies for achieving SACs with excellent intrinsic activity in the context of the ORR mechanism are involved including modulation of coordination environments, the construction of intrinsic defects, and the introduction of dual active sites. Moreover, discussions on improving the loading and utilization of active sites are given. Finally, the current challenges and opportunities for the development of SACs for ORR are presented. [ABSTRACT FROM AUTHOR]

Summary: Eco-friendly, efficient, and durable electrocatalysts from earth-abundant materials are crucial for water splitting through hydrogen and oxygen generation. However, available methods to fabricate electrocatalysts are either hazardous and time-consuming or require expensive equipment, hindering the large-scale, eco-friendly production of artificial fuels. Here, we present a rapid, single-step method for producing MoSx/NiF electrocatalysts with controlled sulfur-vacancies via electric-field-assisted pulsed laser ablation (EF-PLA) in liquid and in-situ deposition on nickel foam, enabling efficient water splitting. Electric-field parameters efficiently control S-vacancy active sites in electrocatalysts. Higher electric fields yield a MoSx/NiF electrocatalyst with a larger density of S-vacancy sites, suited for HER due to lower Gibbs free energy for H∗ adsorption, while lower electric fields produce an electrocatalyst with lower S-vacancy sites, better suited for OER, as shown by both experimental and theoretical results. The present work opens a horizon in designing high-efficiency catalysts, for a wide range of chemical reactions.

Abstract Nitrogen reduction reaction (NRR) is used to convert nitrogen (N2) to ammonia (NH3) at ambient conditions. In general, acidic electrolytes are used to provide protons (H+), however, this leads to low selectivity due to H2 formation via the hydrogen evolution reaction (HER). Recently, it is shown that Ti2N MXene is active and selective for NRR in acidic electrolyte, and operates through a Mars‐van Krevelen (MvK) mechanism. However, the effect of pH on its catalytic performance is not well understood. Here, experiments are performed in varying pH values and relations are developed between pH and performance. The findings of this study indicate that the lowest NRR onset occurs within pH 2 systems exhibiting a nonlinear trend. However, as pH decreases, overpotential decreases, and kinetics increase due to H+ participation. FE values are found to increase as pH increased. These findings will be extended to other materials to design optimal electrolytic systems for NRR.

Summary: Developing active and cost-effective bifunctional electrocatalysts for overall water splitting is challenging but mandatory for renewable energy technologies. We report a high-entropy alloy (HEA) of PtIrCuNiCr as a bifunctional electrocatalyst for overall water splitting, which shows a low overpotential of ca. 190 mV at the current density of 10 mA cm−2. Compared with pure metals, HEAs exhibit remarkable surface strain due to severe lattice distortion in their crystal structures. Theoretical calculations reveal that the strain can regulate the binding energy of intermediates on catalysts by adjusting the metal-metal bonding energy. It pushes the HEA toward the top of volcano plots to achieve superior electrocatalytic activity for both hydrogen and oxygen evolution reactions. The strain effect of HEAs on electrocatalysis can be well engineered by tuning the catalyst radius or configurational entropy. This work renders a systematic strain regulation strategy for designing a high-performance HEA catalyst for overall water splitting.

To understand the role of structure imperfections on the performance of electrochromic transition metal oxide (ETMO) is challenging for the design of efficient smart windows. Herein, we investigate the performance evolution with tunable crystallographic imperfections for rutile TiO2 nanowire film (TNF). Structure imperfections, originating mainly from the copious oxygen deficiency, are apt to cumulatively retard the shuttling ions, resulting in the response rate for raw TNF being less than the half that of TNF annealed at 500 °C. We describe ion accommodation sites as a convolution of normal site and abnormal site, in which the normal site performs reversible coloration but the abnormal site contributes only to charge storage, which gives a rationale for the non‐linear coloration and rate capability loss. These findings give a clear picture of the ion shuttling process, which is insightful for enhancing the electrochromic performance via structure reprogramming. [ABSTRACT FROM AUTHOR]

C(sp2)–C(sp3) bonds comprise the fundamental skeletons of many organic molecules, making their construction one of the most important transformations in synthetic chemistry. Over the past decades, radical-based C(sp2)–C(sp3) cross-coupling reactions have emerged as a straightforward and powerful tool to rapidly increase molecular complexity for numerous applications in biomedical science, chemistry, and materials science. Electrochemistry is regarded as a synthetically appealing alternative to drive redox reactions in a selective and environmentally benign manner. With the flourishing development of organic electrosynthesis, remarkable achievements have been witnessed in radical-mediated aryl/alkenyl C(sp2)–C(sp3) cross-coupling reactions for the synthesis of diverse alkylated (hetero)arenes and 1,2-disubstituted alkenes. In these reactions, the generation of alkyl radicals and their orderly transformation are the keys to success. This review comprehensively summarizes recent progress in electrochemically initiated radical-mediated C(sp2)–C(sp3) cross-coupling reactions, emphasizing the key electrochemically induced step for the generation of alkyl radical species, the scope and limitations of the C(sp2) and C(sp3) coupling partners, and the underlying reaction mechanisms. [ABSTRACT FROM AUTHOR]

[Display omitted] • First study on Eu(III) speciation and electrochemistry in DES, focusing on the impact of various hydrogen bond donors. • Identifies ChCl:1MA DES as the most stable due to strong Eu-Cl and Eu-O interactions. • Cyclic voltammetry and photoluminescence spectroscopy was explored to study Eu(III) coordination. • DFT calculations elucidate metal-ligand interactions in Eu(III) complexes. This study explores the electrochemical properties and speciation of Eu(III) ions in choline chloride (ChCl)-based deep eutectic solvents (DESs), focusing on how different hydrogen bond donors—urea (U), ethylene glycol (EG), and malonic acid (MA)—influence the stability of europium complexes. Employing electrochemical methods, spectroscopic analysis, and theoretical approaches, the research examines how changes in hydrogen bonding during complexation affect Eu(III) coordination. Cyclic voltammetry highlights the role of complex formation and DES viscosity in controlling mass transport and electron transfer rates. Theoretical and experimental data show that the ChCl:1MA DES forms the most stable europium complex, driven by strong hydrogen bonding and robust Eu-DES interactions, as supported by optimized geometries and favorable electrochemical stability. This stability is further confirmed by the high negative binding and formation free energies of Eu(NO 3) 3 ·5H 2 O in all three DES systems. Photoluminescence spectroscopy reveals fluorophore formation due to interactions between hydrogen bonds and functional groups such as –NH 2 , –COOH, and –OH, enhancing the understanding of Eu3+-DES complexes for potential applications in materials science. By clarifying how hydrogen bond donors affect Eu(III) speciation and reactivity, this research advances lanthanide chemistry in DESs and opens avenues for designing Eu(III)-based materials with specialized properties for various technological uses. [ABSTRACT FROM AUTHOR]

In-house electrospun La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3–δ (LSCF) nanofibers have been tested through synchrotron x-ray diffraction and electrochemical impedance spectroscopy (EIS) in the 823–1173 K range, namely in the operating window of intermediate-temperature solid oxide fuel cells. Identical tests have been carried out on commercial LSCF powders, as a control sample. The results demonstrate that the electrospinning manufacturing procedure influences the crystalline properties of the perovskite. The rhombohedral structure (R), stable at room temperature, is retained by nanofibers throughout the whole temperature range, while a rhombohedral to cubic transition (R→C) is detected in powders at ⁓1023 K as a discontinuity in the rhombohedral angle α, accompanied by an abrupt change in oxygen occupation and microstrain. EIS data have a single trend in the nanofibers Arrhenius plot, and two different ones in powders, separated by a discontinuity at the structural transition temperature. Thus, a striking parallel is demonstrated between the variation with temperature of crystallographic features and electrochemical performance. Interestingly, this parallel is found for both nanofiber and granular electrodes. This opens up questions and new perspectives in attributing activation energies derived from EIS tests of LSCF materials to electrochemical processes and/or crystal structure variations. • LSCF nanofibers and powders show different structural and electrochemical features. • A rhombohedral→cubic (R → C) transition occurs in powders at ⁓1023 K. • Nanofibers retain the rhombohedral structure at least up to 1173 K. • A slope change occurs in the EIS Arrhenius plot of powders at the R → C transition. • Electrochemical activation energies are affected by structural changes. [ABSTRACT FROM AUTHOR]

A layer-by-layer approach in the assembly of nanomaterials from the atomic layers electrochemically generated by underpotential deposition was reinforced by the development of the method of multiparametric monitoring of surface-restricted electrochemical reactions based on frequency response analysis under nonstationary conditions. The upd in a wide meaning of this term is not restricted to deposition of a monolayer of one metal onto an electrode of different metal but involves also nonmetals, such as Se and Te, their compounds (CdSe, CdTe, CdS, PbTe, PbSe, Bi2Te3, etc.) and superlattices, such as (Bi2)m(Bi2Te3)n. The experience acquired in the electrochemistry of the underpotential deposition and multilayer assembly can be also helpful in other fields of materials science, such as supercapacitor research, where the frequency response examination of the surface-restricted reactions enables the discrimination between capacitive and noncapacitive currents under conditions preventing from the use of classical impedance spectroscopy and evaluation of energy dissipation in the charge–discharge processes. [ABSTRACT FROM AUTHOR]

Summary: Lithium-ion batteries (LIBs) are among the most promising power sources for electric vehicles, portable electronics and smart grids. In LIBs, the cathode is a major bottleneck, with a particular reference to its low electrical conductivity and Li-ion diffusivity. The coating with carbon layers is generally employed to enhance the electrical conductivity and to protect the active material from degradation during operation. Here, we demonstrate that this layer has a primary role in the lithium diffusivity into the cathode nanoparticles. Positron is a useful quantum probe at the electroactive materials/carbon interface to sense the mobility of Li-ion. Broadband electrical spectroscopy demonstrates that only a small number of Li-ions are moving, and that their diffusion strongly depends on the type of carbon additive. Positron annihilation and broadband electrical spectroscopies are crucial complementary tools to investigate the electronic effect of the carbon phase on the cathode performance and Li-ion dynamics in electroactive materials.

Summary: Ethylene carbonate (EC) in the electrolyte is not stable in cells operated at high voltage (≥4.4V) or with Li metal anode, which greatly reduce the energy density and lifetime of the rechargeable lithium battery. Herein, an EC-free linear alkyl carbonate-based electrolyte is developed, which enables the high-voltage (≥4.4V) and low-temperature (−30°C) application of Ni-rich cathode (LiNi0.8Mn0.1Co0.1O2, NCM811). The EC-free system, consisting of LiPF6 and LiNO3 in ternary linear alkyl carbonates, possesses low viscosity, weakly solvated structure, and high interfacial stability with both the Ni-rich cathode and the Li metal anode to avoid continuous electrode/electrolyte side reactions and metal dissolution from the cathode. As a result, the Li||NCM811 cell delivers remarkable capacity retention of 93 ± 0.5% at the voltage of 4.4V and 88 ± 0.6% at 4.5V over 100 cycles. This study provides very encouraging perspective to develop EC-free carbonate-based electrolyte for high-voltage and low-temperature application in high-energy-density rechargeable lithium batteries.

Phosphorus-containing compounds have a huge synthetic potential because of their wide application in pharmaceuticals, biology, agrochemistry, organic synthesis, and materials science. The search for new selective reactions for their preparation requires a deeper understanding of the properties and reactivity of key intermediates, which include phosphorus-centered radicals. Of particular interest are the ways to stabilize such radicals, which have unusual physical properties. This review analyzes and summarizes basic achievements and trends in both the generation of highly reactive phosphorus radicals and their involvement in practically significant synthesis reactions, primarily the formation of phosphorus–carbon bonds, and the pathways for the synthesis of stable radicals, their physicochemical properties, and magnetic resonance parameters. Despite the long historical development of research, important achievements in this area have been made over the past decade. [ABSTRACT FROM AUTHOR]

In this work, the synthesis of Nylon‐6.6 together with silver nanoparticles (presumably Ag2O, Ag NPs) was carried out at a polarized liquid‐liquid interface (LLI). The reduction of silver ions to Ag‐NPs was driven by an electrochemically controlled electron transfer reaction between silver cations initially dissolved in the aqueous phase and ferrocene species present in the organic phase. The formation of Ag2O is assumed to originate from Ag+ precipitation to AgOH further converted into Ag2O. The polyamide formation was derived from the interfacial polycondensation reaction happening between 1,6‐diaminohexane and adipoyl chloride. We studied the possibility to form given material simultaneously (interfacial polycondensation and Ag+ reduction occurring in one step) and sequentially (electrochemical Ag+ reduction by ferrocene from the organic phase was performed after polyamide deposition). The Ag‐based NPs‐polyamide material was synthesized at the macroscopic and microscopic LLI. As the support for the latter, fiberglass membranes was used. The resulting material was characterized by infra‐red (IR) spectroscopy and scanning electron microscopy (SEM). [ABSTRACT FROM AUTHOR]

Summary: Ammonia is a promising carbon-free hydrogen carrier. Owing to their nickel-rich anodes and high operating temperatures, solid oxide fuel cells (SOFCs) can directly utilize NH3 fuel—direct-ammonia SOFCs (DA-SOFCs). Lowering the operating temperature can diversify application areas of DA-SOFCs. We tested direct-ammonia operation using two types of thin-film SOFCs (TF-SOFCs) under 500 to 650°C and compared these with a conventional SOFC. The TF-SOFC with a nickel oxide gadolinium-doped ceria anode achieved a peak power density of 1330 mW cm−2 (NH3 fuel under 650°C), which is the best performance reported to date. However, the performance difference between the NH3 and H2 operations was significant. Electrochemical impedance analyses, ammonia conversion quantification, and two-dimensional multi-physics modeling suggested that reduced ammonia conversion at low temperatures is the main cause of the performance gap. A comparative study with previously reported DA-SOFCs clarified that incorporating a more active ammonia decomposition catalyst will further improve low-temperature DA-SOFCs.