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The adoption of green hydrogen economy is an indispensable necessity in the current global scenario of environment and energy security. In this endeavor, ammonia is poised to play a key vector of hydrogen to mitigate the challenges arising from transportation, storage and safety. Besides containing a high volumetric and gravimetric hydrogen density, NH3 decomposition into H2 for onsite utilization as a distributed energy source is devoid of greenhouse gases production. In this endeavor, significant technological advancements have been made for in situ production of H2 from NH3 decomposition and the use of NH3 in fuel cell devices to produce electricity. The ammonia decomposition methods to produce H2 mainly involve thermocatalytic, oxidative, electrocatalytic and photocatalytic, among which the catalyst assisted thermal cracking of NH3 has been widely investigated. The research progress in electrolysis of NH3 has been notable in the last couple of years and provides a low‐cost alternative to produce H2 at room temperature. In the area of device development, solid oxide fuel cells (SOFC) have witnessed rapid development in the performances and stability, as ammonia is completely decomposed into H2 and N2 at high operating temperature above ~700 °C. [ABSTRACT FROM AUTHOR]

Pentavalent uranium compounds are key components of uranium's redox chemistry and play important roles in environmental transport. Despite this, well‐characterized U(V) compounds are scarce primarily because of their instability with respect to disproportionation to U(IV) and U(VI). In this work, we provide an alternate route to incorporation of U(V) into a crystalline lattice where different oxidation states of uranium can be stabilized through the incorporation of secondary cations with different sizes and charges. We show that iriginite‐based crystalline layers allow for systematically replacing U(VI) with U(V) through aliovalent substitution of 2+ alkaline‐earth or 3+ rare‐earth cations as dopant ions under high‐temperature conditions, specifically Ca(UVIO2)W4O14 and Ln(UVO2)W4O14 (Ln=Nd, Sm, Eu, Gd, Yb). Evidence for the existence of U(V) and U(VI) is supported by single‐crystal X‐ray diffraction, high energy resolution X‐ray absorption near edge structure, X‐ray photoelectron spectroscopy, and optical absorption spectroscopy. In contrast with other reported U(V) materials, the U(V) single crystals obtained using this route are relatively large (several centimeters) and easily reproducible, and thus provide a substantial improvement in the facile synthesis and stabilization of U(V). [ABSTRACT FROM AUTHOR]

High‐throughput experimentation, a well‐established and powerful tool in the field of heterogeneous catalysis screening, has been extended to the field of electrochemistry. A parallel and modular high‐throughput screening platform was designed, involving the development of a new modular electrochemical flow cell by the Fraunhofer Institute for Microengineering and Microsystems (IMM) in cooperation with hte GmbH and IEK‐9 / FZ Jülich GmbH. Here, this platform is introduced for alkaline water electrolysis, showing initial results that underline the flexibility, comparability, and accuracy of the experiments. [ABSTRACT FROM AUTHOR]

In situ transmission electron microscopy (TEM) is increasingly utilized by researchers to explore various electrochemical applications in the quest to address climate change, aiming to comprehend underlying mechanisms and enhance performance. However, the conventional Pt microelectrode commonly used in in situ TEM poses limitations due to its low electron transparency and high catalytic activity. In this study, titanium nitride (TiNx) is introduced as a novel microelectrode material that can be fabricated following typical cleanroom processes. Through in situ Zn and Cu electrodeposition studies, it is shown how the low catalytic activity and higher electron transparency of TiNx enable obtaining stable electrochemical cycling and quantify the deposition on top of microelectrode in TEM mode, highlighting the benefit of TiNx microelectrodes for different in situ TEM studies. [ABSTRACT FROM AUTHOR]

Anode‐free Li‐metal batteries are of significant interest to energy storage industries due to their intrinsically high energy. However, the accumulative Li dendrites and dead Li continuously consume active Li during cycling. That results in a short lifetime and low Coulombic efficiency of anode‐free Li‐metal batteries. Introducing effective electrolyte additives can improve the Li deposition homogeneity and solid electrolyte interphase (SEI) stability for anode‐free Li‐metal batteries. Herein, we reveal that introducing dual additives, composed of LiAsF6 and fluoroethylene carbonate, into a low‐cost commercial carbonate electrolyte will boost the cycle life and average Coulombic efficiency of NMC||Cu anode‐free Li‐metal batteries. The NMC||Cu anode‐free Li‐metal batteries with the dual additives exhibit a capacity retention of about 75% after 50 cycles, much higher than those with bare electrolytes (35%). The average Coulombic efficiency of the NMC||Cu anode‐free Li‐metal batteries with additives can maintain 98.3% over 100 cycles. In contrast, the average Coulombic efficiency without additives rapidly decline to 97% after only 50 cycles. In situ Raman measurements reveal that the prepared dual additives facilitate denser and smoother Li morphology during Li deposition. The dual additives significantly suppress the Li dendrite growth, enabling stable SEI formation on anode and cathode surfaces. Our results provide a broad view of developing low‐cost and high‐effective functional electrolytes for high‐energy and long‐life anode‐free Li‐metal batteries. [ABSTRACT FROM AUTHOR]

With growing demand for energy storage alternatives, silicon‐air batteries have gained attention due to their impressive theoretical specific energy (8470 Wh kgSi−1) and theoretical specific capacity (3820 mAh gSi−1). Although current challenges, such as corrosion, low anode mass conversion efficiency, and limited power output, restrict their practical use and commercialization potential, the ongoing advancement of materials and efficient electronic components open up a range of potential applications for Silicon‐air (Si‐air) batteries. This study investigates the feasibility of employing a single alkaline or non‐aqueous silicon‐air battery to power low‐power transient electronic device. Initially, their electrochemical behavior, corrosion parameters, and performance were assessed, yielding crucial parameters for the circuit design. Short‐term galvanostatic discharge experiments demonstrated the effective operation of Si‐air battery under varying current densities in both electrolytes without passivation issues. Subsequently, a proof‐of‐concept for self‐consumed and self‐destructive transient electronic device is presented, wherein a full‐cell Si‐air battery with non‐aqueous and aqueous electrolytes was operated while powering a light‐emitting diode (LED) as a practical illustrative application. [ABSTRACT FROM AUTHOR]

In this work, the performance, electrochemical processes, and stability of GDC (Ce0.8Gd0.2O1.9) fuel electrode containing single cells (GDC/8YSZ/GDC/LSCF) were examined in CO2 electrolysis conditions. The current density and area specific resistance is determined for different operation conditions. The examined cells showed a higher performance compared to state‐of‐the‐art Ni−YSZ fuel electrode (Ni‐YSZ/8YSZ/GDC/LSCF) based single cells with a similar production route. Furthermore, the cells were examined by means of electrochemical impedance spectroscopy (EIS) and the recorded data were evaluated by the distribution of relaxation times (DRT) analysis. An equivalent circuit model (ECM) consisting of four time constants and a Gerischer impedance (LR−RQ1−RQ2−G−RQ4−RQ5) was established to gain further insight into the individual processes in the cells. For instance, the low–frequency process P5 referring to RQ5 is the rate‐determining step in CO2 electrolysis and is assigned to a surface reaction including the charge transfer and possibly the gas diffusion in the GDC fuel electrode. A long–term stability test was performed in CO2 electrolysis conditions at 900 °C with a constant current load of −0.5 A ⋅ cm−2 for up to 1200 h. A degradation rate of 62 mV ⋅ kh−1 was observed. By EIS analysis, a similar contribution of the ohmic and polarization resistances to the degradation was determined. The low–frequency process P5 and thus the surface reaction including the charge transfer in the GDC fuel electrode is contributing most to the increase in polarization resistance. After the long–term stability test, scanning electron microscopy (SEM) analysis was carried out and a coarsening of GDC particles in the fuel electrode was observed. [ABSTRACT FROM AUTHOR]

A key task in today's inorganic synthetic chemistry is to develop effective reactions, routes, and associated techniques aiming to create new functional materials with specifically desired multilevel structures and properties. Herein, we report an ultrathin two‐dimensional layered composite of graphene ribbon and silicate via a simple and scalable one‐pot reaction, which leads to the creation of a novel carbon‐metal‐silicate hybrid family: carbosilicate. The graphene ribbon is in situ formed by unzipping carbon nanotubes, while the ultrathin silicate is in situ obtained from bulk silica or commercial glass; transition metals (Fe or Ni) oxidized by water act as bridging agent, covalently bonding the two structures. The unprecedented structure combines the superior properties of the silicate and the nanocarbon, which triggers some specific novel properties. All processes during synthesis are complementary to each other. The associated synergistic chemistry could stimulate the discovery of a large class of more interesting, functionalized structures and materials. [ABSTRACT FROM AUTHOR]

Aiming to advance the technical maturity of CO2 electrolysis to formic acid, various gas diffusion layers (GDLs) are investigated for their suitability as carbon‐based substrate for gas diffusion electrodes (GDEs) and their effect on the electroreduction of CO2 to formate. Particular attention lies on the elucidation for the effect of the GDL thickness, hydrophobic treatment, and presence of a microporous layer (MPL) on the GDE performance in terms of Faradaic efficiency. Based on the investigation it is found that the GDL thickness has no discernible influence on the Faradaic efficiency, while a GDE with a hydrophobic treatment of 10 % PTFE outperforms a GDE based on a GDL with 30 % PTFE. Furthermore, the presence of a MPL is found to be of marked importance to achieve relevant current densities given its effect on the focus of the catalyst layer on the GDE surface after spray coating, the wetting, and the electrical conductivity. [ABSTRACT FROM AUTHOR]

Reducing non‐radiative recombination energy loss (ΔE3) is one key to boosting the efficiency of organic solar cells. Although the recent studies have indicated that the Y‐series asymmetric acceptors‐based devices featured relatively low ΔE3, the understanding of the energy loss mechanism derived from molecular structure change is still lagging behind. Herein, two asymmetric acceptors named BTP‐Cl and BTP‐2Cl with different terminals were synthesized to make a clear comparative study with the symmetric acceptor BTP‐0Cl. Our results suggest that asymmetric acceptors exhibit a larger difference of electrostatic potential (ESP) in terminals and semi‐molecular dipole moment, which contributes to form a stronger π–π interaction. Besides, the experimental and theoretical studies reveal that a lower ESP‐induced intermolecular interaction can reduce the distribution of PM6 near the interface to enhance the built‐in potential and decrease the charge transfer state ratio for asymmetric acceptors. Therefore, the devices achieve a higher exciton dissociation efficiency and lower ΔE3. This work establishes a structure‐performance relationship and provides a new perspective to understand the state‐of‐the‐art asymmetric acceptors. [ABSTRACT FROM AUTHOR]

Efficiently improving the moisture stability of β‐Li3PS4 materials could significantly reduce production costs and eventually enable the mass application. Nanoporous multiphase β‐Li3PS4 materials prepared via solvent‐assistant routes usually contain solvent or solvent decomposition segments associated with the amorphous Li3PS4 phase in their structures. Herein, the solvent ethyl propionate (EP) remains in the β‐Li3PS4 even after 220 h of annealing at 220°C. The possibility of tuning the moisture stability of β‐Li3PS4 by adjusting the content of the solvent is investigated by environmental scanning electron microscopy (ESEM) combined with other structural analysis techniques. The results demonstrated that the hydrogen‐containing amorphous Li3PS4 not only stabilizes the β‐phase at room temperature but also improves the moisture stability of the material. Although the rapid hydrolysis occurs on the surface of solvent‐containing β‐Li3PS4 materials under ambient conditions within 10 s, with 4 wt% EP content, the material can be exposed to 1.6% relative humidity (R.H.) for at least 8 h without any structural or microstructural change. Even with the lower amount of EP (1.2 wt%) in the Li3PS4 structure, the material can withstand 1% R.H. for more than 8 h, which allows the material to be manufactured in a dry room. Our observation proposes a simple method to slightly modify the moisture stability of β‐Li3PS4 to match the different manufacturing conditions. [ABSTRACT FROM AUTHOR]

A direct current in an electrochemical cell with a diluted liquid electrolyte leads to the displacement of ions within the solvent, while diffusion works against the resulting concentration differences. This study aims to experimentally evaluate a physicochemical ion transport model (source code provided) that describes current‐driven concentration gradients in diluted electrolytes. Hereto, an aqueous 0.1 M CuSO4 electrolyte between metallic copper electrodes serves as an experimental test system. Spatially resolved optical measurements are used to monitor the evolution of the ion concentration gradient in the electrolyte. Moreover, measured limited currents are related to computationally modeled concentration gradients. A constant parameterization of the diffusion coefficient, molar conductivity and ion transport number lead to a slight overestimation of the cathodic ion depletion and cell resistance, whereas a literature data based concentration dependent parameterization matches better to the measured data. The limited current is considered under a computational parameter variation and thereby related to the physicochemical impact of different electrolyte properties on the ion transport. This approach highlights the differences between purely diffusion limited currents and the limited current resulting from the combined electric field and diffusion driven ion motion. A qualitative schematic sketch of the physical mechanisms of the ion movement is presented to illustrate the current driven ion displacement in liquid electrolytes. [ABSTRACT FROM AUTHOR]

Li7La3Zr2O12 (LLZO)‐based all‐solid‐state Li batteries (SSLBs) are very attractive next‐generation energy storage devices owing to their potential for achieving enhanced safety and improved energy density. However, the rigid nature of the ceramics challenges the SSLB fabrication and the afterward interfacial stability during electrochemical cycling. Here, a promising LLZO‐based SSLB with a high areal capacity and stable cycle performance over 100 cycles is demonstrated. In operando transmission electron microscopy (TEM) is used for successfully demonstrating and investigating the delithiation/lithiation process and understanding the capacity degradation mechanism of the SSLB on an atomic scale. Other than the interfacial delamination between LLZO and LiCoO2 (LCO) owing to the stress evolvement during electrochemical cycling, oxygen deficiency of LCO not only causes microcrack formation in LCO but also partially decomposes LCO into metallic Co and is suggested to contribute to the capacity degradation based on the atomic‐scale insights. When discharging the SSLB to a voltage of ≈1.2 versus Li/Li+, severe capacity fading from the irreversible decomposition of LCO into metallic Co and Li2O is observed under in operando TEM. These observations reveal the capacity degradation mechanisms of the LLZO‐based SSLB, which provides important information for future LLZO‐based SSLB developments. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries are one of the most promising alternatives for advanced battery systems due to the merits of extraordinary theoretical specific energy density, abundant resources, environmental friendliness, and high safety. However, the sluggish sulfur reduction reaction (SRR) kinetics results in poor sulfur utilization, which seriously hampers the electrochemical performance of Li–S batteries. It is critical to reveal the underlying reaction mechanisms and accelerate the SRR kinetics. Herein, the critical issues of SRR in Li–S batteries are reviewed. The conversion mechanisms and reaction pathways of sulfur reduction are initially introduced to give an overview of the SRR. Subsequently, recent advances in catalyst materials that can accelerate the SRR kinetics are summarized in detail, including carbon, metal compounds, metals, and single atoms. Besides, various characterization approaches for SRR are discussed, which can be divided into three categories: electrochemical measurements, spectroscopic techniques, and theoretical calculations. Finally, the conclusion and outlook part gives a summary and proposes several key points for future investigations on the mechanisms of the SRR and catalyst activities. This review can provide cutting‐edge insights into the SRR in Li–S batteries. [ABSTRACT FROM AUTHOR]

In solid oxide cells, Sr segregation has been correlated with degradation. Yet, the atomistic mechanism remains unknown. Here we begin to localize the origin of Sr surface nucleation by combining force field based simulations, energy dispersive X‐ray spectroscopy (EDX), and multi‐variate statistical analysis. We find increased ion mobility in the complexion between yttria‐stabilized zirconia and strontium‐doped lanthanum manganite. Furthermore, we developed a robust and automated routine to detect localized nucleation seeds of Sr at the complexion surface. This hints at a mechanism originating at the complexion and requires in‐depth studies at the atomistic level, where the developed routine can be beneficial for analyzing large hyperspectral EDX datasets. [ABSTRACT FROM AUTHOR]

Battery modeling has become increasingly important with the intensive development of Li‐ion batteries (LIBs). The porous electrode model, relating battery performances to the internal physical and (electro)chemical processes, is one of the most adopted models in scientific research and engineering fields. Since Newman and coworkers' first implementation in the 1990s, the porous electrode model has kept its general form. Soon after that, many publications have focused on the applications to LIBs. In this review, the applications of the porous electrode model to LIBs are systematically summarized and discussed. With this model, various internal battery properties have been studied, such as Li+ concentration and electric potential in the electrolyte and electrodes, reaction rate distribution, overpotential, and impedance. When coupled with thermal, mechanical, and aging models, the porous electrode model can simulate the temperature and stress distribution inside batteries and predict degradation during battery operation. With the help of state observers, the porous electrode model can monitor various battery states in real‐time for battery management systems. Even though the porous electrode models have multiple advantages, some challenges and limitations still have to be addressed. The present review also gives suggestions to overcome these limitations in future research. [ABSTRACT FROM AUTHOR]

The mechanism of reversible lithium intercalation in graphite anodes is still not fully understood. In operando Raman spectroscopy provides a sensitive means to monitor structural changes during the intercalation process. Analysis of the D‐band to G‐band intensity ratio (D/G ratio) is a common method to study the structure of carbon materials. However, this approach is complicated for the investigation of graphite anodes during battery cycling, as the D‐band disappears with the onset of lithium intercalation. To circumvent this issue, the D/G ratio can be replaced by using the G‐band full‐width‐at‐half‐maximum (FWHM). In this study, an investigation of the G‐band FWHM during battery cell cycling is demonstrated as an alternative to monitor the intercalation of lithium into a graphite electrode. It was observed that lithium intercalation already occurs to a small extent during solid–electrolyte interphase (SEI) formation and that the formation of staged intercalation compounds leads to a continuous deformation of the boundary graphene layer. [ABSTRACT FROM AUTHOR]

The development of highly selective adsorbents for CO2 is a key part to advance separation by adsorption as a viable technique for CO2 capture. In this work, polyacrylonitrile (PAN) based carbon nanofibers (CNFs) were investigated for their CO2 separation capabilities using dynamic gas adsorption. The CNFs were prepared by electrospinning and subsequent carbonization at various temperatures ranging from 600 to 1000 °C. A thorough investigation of the CO2/N2 selectivity resulted in measured values of 53–106 at 1 bar and 25 °C on CNFs carbonized at 600, 700, or 800 °C. Moreover, the selectivity increased with lower measurement temperatures and lower CO2 partial pressures, reaching values up to 194. Further analysis revealed high long‐term stability with no degradation over 300 cycles and fast adsorption kinetics for CNFs carbonized at 600 or 700 °C. These excellent properties make PAN‐based CNFs carbonized at 600 or 700 °C promising candidates for the capture of CO2. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER) on iron is a parasitic side reaction for the reduction of iron (hydr)oxide in alkaline electrolyte, which lowers the Coulombic efficiency of iron‐based batteries. Tackling this issue, here we investigate the HER on iron electrodes by in situ gas chromatography, allowing for a quantitative correlation of the applied electrode potential and the resulting hydrogen evolution. As a result, it is shown that the HER follows a distinctive profile corresponding to the electrode potential and changes depending on the state of the iron electrode formation. Moreover, it is shown that the charging efficiency of the iron electrode can be increased by an alteration of the charging procedure, i. e., a more negative cut‐off potential for the discharge and a potential limitation for the recharge. In this study, a charging efficiency of 96.7 % is achieved, using an optimized charging procedure for a formed carbonyl iron electrode containing 8.5 wt.% of Bi2S3. [ABSTRACT FROM AUTHOR]

The article titled "Cover Feature: Unveiling the Potential of Silicon-Air Batteries for Low-Power Transient Electronics: Electrochemical Insights and Practical Application" discusses the use of silicon-air batteries as a groundbreaking solution for powering transient electronics. These batteries incorporate self-destruction mechanisms to enhance data security and have a controlled device lifespan. After being used as fuel, the silicon in these batteries can be transformed into silica sand, completing its life cycle. This integration of energy storage and electronics offers practical advancements in technology and data security. The article is authored by Y. E. Durmus and co-workers. [Extracted from the article]

The growing demand for sustainable energy storage devices requires rechargeable lithium‐ion batteries (LIBs) with higher specific capacity and stricter safety standards. Ni‐rich layered transition metal oxides outperform other cathode materials and have attracted much attention in both academia and industry. Lithium‐ion batteries composed of Ni‐rich layered cathodes and graphite anodes (or Li‐metal anodes) are suitable to meet the energy requirements of the next generation of rechargeable batteries. However, the instability of Ni‐rich cathodes poses serious challenges to large‐scale commercialization. This paper reviews various degradation processes occurring at the cathode, anode, and electrolyte in Ni‐rich cathode‐based LIBs. It highlights the recent achievements in developing new stabilization strategies for the various battery components in future Ni‐rich cathode‐based LIBs. [ABSTRACT FROM AUTHOR]

Once nanomaterials have been synthesized, inducing further structural modifications is challenging. However, being able to do so in a controlled manner is crucial. In this context, germanium nanowires are irradiated in situ within a transmission electron microscope (TEM) by a 300 keV xenon ion beam at temperatures ranging from room temperature (RT) to 500 °C. The ion irradiation is performed in situ and the evolution of nanowires during irradiation is monitored. At 300 °C and below, where the temperature is low enough to allow amorphization, the ion beam causes the formation of nanostructures within the nanowires. Formation of nanopores and swelling of nanowires is observed for a very low fluence of 2.2 × 1014 and up to 4.2 × 1015 ions cm−2. At higher fluences, the thickness of the nanowires decreases, the nanowires lose their wire‐like cylindrical shape and the nanostructuring caused by the ion beam becomes more complex. The nanostructures are observed to be stable upon crystallization when the nanowires are annealed at 530 °C. Furthermore, in situ imaging allows the growth of nanopores during irradiation to be followed at RT and at 300 °C providing valuable insights into the mechanism responsible for the nanostructuring. [ABSTRACT FROM AUTHOR]

The influence of ethylenediaminetetraacetic acid (EDTA) electrolyte additive on the performance of Zn−air batteries with near‐neutral chloride‐based electrolytes was examined for primary and secondary batteries. The electrochemical measurements indicated that Zn is not completely active in neat 2 M NaCl, but still could be discharged up to 1 mA cm−2 around −1.0 VAg/AgCl. The characterization of the Zn surfaces revealed the existence of a passive film consisting of Simonkolleite, Zn(OH)2, and/or ZnO. The EDTA additive enhanced the discharge voltages by 200 mV to −1.2 VAg/AgCl indicating an active Zn surface. The effect of EDTA is explained by its chelation abilities with Zn2+ before formation of hydroxide or oxide species. The Zn−air cells with EDTA were operated up to 930 h with specific energies up to 840 Wh kgZn−1. The cells could also be cycled up to 70 cycles while providing enhanced discharge voltages at 1.15 V over 50 cycles. The positive effect of EDTA is dependent on the amount of free EDTA molecules. Nevertheless, the Zn−air cells showed better performance in terms of higher discharge voltage, discharge energies, and lower overpotentials in presence of EDTA. [ABSTRACT FROM AUTHOR]

In solid oxide fuel cell (SOFC) system with anode‐exhaust gas recirculation (AEGR), a part of the depleted anode‐exhaust gas is recirculated and mixed with fresh natural gas prior to entering the reformer, resulting in a high potential of direct current‐efficiencies of up to 65%. However, for SOFC systems, it is of crucial importance to monitor relevant characteristic parameters and keep them within safe and durable operating limits. Such characteristic parameters are oxygen‐to‐carbon‐ratio and fuel utilization, which must not exceed system‐specific thresholds. Monitoring and control of these characteristic parameters is not trivial and a challenging task due to the enhanced system complexity. The authors present an approach and studies for determination and controlling characteristic parameters in an SOFC system with AEGR based on oxygen sensors. Therefore, the oxygen sensors, being a mature and easily available technology, are aimed to be in the fuel gas path at anode inlet and outlet of an SOFC‐stack. Analytical correlations of the output value of oxygen sensors to characteristic parameters and simulative studies on the basis of a reference natural gas composition are shown. Additionally, first results of experimental studies of oxygen sensors in representative gas compositions for the anode inlet and outlet of an SOFC system with AEGR are presented. [ABSTRACT FROM AUTHOR]

Rapid deactivation presently limits a wide spread use of high‐temperature solid oxide cells (SOCs) as otherwise highly efficient chemical energy converters. With deactivation triggered by the ongoing conversion reactions, an atomic‐scale understanding of the active triple‐phase boundary between electrolyte, electrode, and gas phase is essential to increase cell performance. Here, a multi‐method approach is used comprising transmission electron microscopy and first‐principles calculations and molecular simulations to untangle the atomic arrangement of the prototypical SOC interface between a lanthanum strontium manganite (LSM) anode and a yttria‐stabilized zirconia (YSZ) electrolyte in the as‐prepared state after sintering. An interlayer of self‐limited width with partial amorphization and strong compositional gradient is identified, thus exhibiting the characteristics of a complexion that is stabilized by the confinement between two bulk phases. This offers a new perspective to understand the function of SOCs at the atomic scale. Moreover, it opens up a hitherto unrealized design space to tune the conversion efficiency. [ABSTRACT FROM AUTHOR]

Dendrite formation and growth remains a major obstacle toward high‐performance all solid‐state batteries using Li metal anodes. The ceramic Li(1+x)Al(x)Ti(2−x)(PO4)3 (LATP) solid‐state electrolyte shows a higher than expected stability against electrochemical decomposition despite a bulk electronic conductivity that exceeds a recently postulated threshold for dendrite‐free operation. Here, transmission electron microscopy, atom probe tomography, and first‐principles based simulations are combined to establish atomistic structural models of glass‐amorphous LATP grain boundaries. These models reveal a nanometer‐thin complexion layer that encapsulates the crystalline grains. The distinct composition of this complexion constitutes a sizable electronic impedance. Rather than fulfilling macroscopic bulk measures of ionic and electronic conduction, LATP might thus gain the capability to suppress dendrite nucleation by sufficient local separation of charge carriers at the nanoscale. [ABSTRACT FROM AUTHOR]

Electrospun carbon nanofibers (CNFs) exhibit a decent CO2 sorption capacity and outstanding CO2/N2 selectivity. In this work, the sorption rate as another practically relevant parameter for CO2 adsorption is analyzed for different carbonization temperatures. Equilibration curves obtained from different CO2 sorption isotherms are discussed qualitatively and quantitatively, employing empirical models for pseudo‐first‐ and second‐order reactions. The sorption rate constants are found to be highly dependent on the carbonization temperature of the CNFs and the applied pressure during the measurement. Furthermore, two distinct processes of sorption are observed, which are attributed to different sorption sites on the surface and the inner volume of the CNFs. [ABSTRACT FROM AUTHOR]

The concept of an integrated power‐to‐gas (P2G) process was demonstrated for renewable energy storage by converting renewable electrical energy to synthetic fuels. Such a dynamically integrated process enables direct production of synthetic natural gas (SNG) from CO2 and H2O. The produced SNG can be stored or directly injected into the existing natural gas network. To study process integration, operating parameters of the high‐temperature solid oxide electrolysis cell (SOEC) producing syngas (H2+CO) mixtures through co‐electrolysis and a fixed bed reactor for syngas methanation of such gas mixtures were first optimized individually. Reactor design, operating conditions, and enhanced SNG selectivity were the main targets of the study. SOEC experiments were performed on state‐of‐the‐art button cells. Varying operating conditions (temperature, flow rate, gas mixture and current density) emphasized the capability of the system to produce tailor‐made syngas mixtures for downstream methanation. Catalytic syngas methanation was performed using hydrotalcite‐derived 20 %Ni‐2 %Fe/(Mg,Al)Ox catalyst and commercial methanation catalyst (Ni/Al2O3) as reference. Despite water in the feed mixture, SNG with high selectivity (≥90 %) was produced at 300 °C and atmospheric pressure. An adequate rate of syngas conversion was obtained with H2O contents up to 30 %, decreasing significantly for 50 % H2O in the feed. Compared to the commercial catalyst, 20 %Ni‐2 %Fe/(Mg,Al)Ox enabled a higher rate of COx conversion. [ABSTRACT FROM AUTHOR]

Electrochemical strain microscopy (ESM) is a distinguished method to characterize Li‐ion mobility in energy materials with extremely high spatial resolution. The exact origin of the cantilever deflection when the technique is applied on solid state electrolytes (SSEs) is currently discussed in the literature. Understanding local properties and influences on ion mobility in SSEs is of utmost importance to improve such materials for next generation batteries. Here, the exact signal formation process of ESM when applied on sodium super ionic conductor (NASICON)‐type SSE containing Na‐ and Li‐ions is investigated. Changes in the dielectric properties, which are linked to the local chemical composition, are found to be responsible for the observed contrast in the deflection of the cantilever instead of a physical volume change as a result of Vegard´s Law. The cantilever response is strongly reduced in areas of high sodium content which is attributed to a reduction of the tip‐sample capacitance in comparison to areas with high lithium content. This is the first time a direct link between electrostatic forces in contact mode and local chemical information is demonstrated on SSEs. The results open up new possibilities in information gain since dielectric properties are sensitive to subtle changes in local chemical composition. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (Li–S) have become a viable alternative to future energy storage devices. The electrochemical reaction based on lithium and sulfur promises an extraordinary theoretical energy density, which is far higher than current commercialized Li‐ion batteries. However, the principal disadvantage impeding the success of Li–S batteries lies in the severe leakage and migration of soluble lithium polysulfide intermediates out of cathodes upon cycling. The loss of active sulfur species incurs significant capacity decay and poor battery lifespans. Considerable efforts have been devoted to developing various sulfur host materials that can effectively anchor lithium polysulfides. Herein, a comprehensive review is presented of recent advances in sulfur host materials. On the basis of the electrochemistry of Li–S batteries, the strategies for anchoring polysulfides are systematically categorized into physical confinement and chemical bonding. The structural merits of various sulfur host materials are highlighted, and the interaction mechanisms with sulfur species are discussed in detail, which provides valuable insights into the rational design and engineering of advanced sulfur host materials facilitating the commercialization of Li–S batteries. Future challenges and promising research prospects for sulfur host materials are proposed at the end of the review. [ABSTRACT FROM AUTHOR]

Extensive efforts have been made to improve the Li‐ionic conductivity of solid electrolytes (SE) for developing promising all‐solid‐state Li‐based batteries (ASSB). Recent studies suggest that minimizing the existing interface problems is even more important than maximizing the conductivity of SE. Interfaces are essential in ASSB, and their properties significantly influence the battery performance. Interface problems, arising from both physical and (electro)chemical material properties, can significantly inhibit the transport of electrons and Li‐ions in ASSB. Consequently, interface problems may result in interlayer formation, high impedances, immobilization of moveable Li‐ions, loss of active host sites available to accommodate Li‐ions, and Li‐dendrite formation, all causing significant storage capacity losses and ultimately battery failures. The characteristic differences of interfaces between liquid‐ and solid‐type Li‐based batteries are presented here. Interface types, interlayer origin, physical and chemical structures, properties, time evolution, complex interrelations between various factors, and promising interfacial tailoring approaches are reviewed. Furthermore, recent advances in the interface‐sensitive or depth‐resolved analytical tools that can provide mechanistic insights into the interlayer formation and strategies to tailor the interlayer formation, composition, and properties are discussed. [ABSTRACT FROM AUTHOR]

Even though advanced ceramics are widely applied as consumables in semiconductor etching processes, the erosion mechanisms and connected surface phenomena are not fully understood. Through the interaction with reactive species and ion bombardment during the plasma exposure, oxide ceramic materials like Y2O3 are eroded by a physicochemical mechanism. In this study, fundamental phenomena of surface‐plasma interactions were investigated directly at the surface as well as in the near‐surface region after exposure to fluorine‐based etching plasmas. A straightforward re‐localization technique was used to investigate the microstructural features before and after the plasma exposure for up to 2 hours. Electron microscopy methods (scanning electron microscopy, electron backscatter diffraction) were coupled with atomic force microscopy, secondary ion mass spectroscopy, and transmission electron microscopy to study the surface topography and the corresponding reaction layer. Direct correlation of the microstructure before plasma exposure with the surface topography reveals a novel orientation‐dependent erosion mechanism that forms plateau‐like structures. Furthermore, the in‐depth analysis of the near‐surface area highlights the influence of the applied bias voltage on the physical damage and chemical gradient formation due to plasma exposure. The combined investigation of surface morphology and near‐surface properties reveals new fundamental aspects of the erosion behavior of polycrystalline yttria in CF4‐based etching plasmas. [ABSTRACT FROM AUTHOR]

Water electrolysis is the key to a decarbonized energy system, as it enables the conversion and storage of renewably generated intermittent electricity in the form of hydrogen. However, reliability challenges arising from titanium‐based porous transport layers (PTLs) have hitherto restricted the deployment of next‐generation water‐splitting devices. Here, it is shown for the first time how PTLs can be adapted so that their interface remains well protected and resistant to corrosion across ≈4000 h under real electrolysis conditions. It is also demonstrated that the malfunctioning of unprotected PTLs is a result triggered by additional fatal degradation mechanisms over the anodic catalyst layer beyond the impacts expected from iridium oxide stability. Now, superior durability and efficiency in water electrolyzers can be achieved over extended periods of operation with less‐expensive PTLs with proper protection, which can be explained by the detailed reconstruction of the interface between the different elements, materials, layers, and components presented in this work. [ABSTRACT FROM AUTHOR]

Carbon nanofibers (CNFs) derived from electrospun polyacrylonitrile (PAN) were investigated with respect to their gas adsorption properties. By employing CO2 adsorption measurements, it is shown that the adsorption capacity and selectivity of the fibers can be tailored by means of the applied carbonization temperature. General pore properties of the CNFs were identified by Ar adsorption measurements, whereas CO2 adsorption measurements provided information about the ultramicroporosity, adsorption energies, and adsorption capacities. Ideal adsorbed solution theory (IAST) selectivities under practically relevant conditions were determined by evaluation of single‐component data for N2 and CO2. Especially for low carbonization temperatures, the CNFs exhibit very good low‐pressure adsorption performance and excellent CO2/N2 IAST selectivities of 350 at 20 mbar and 132 at 1 bar, which are attributed to a molecular‐sieve effect in very narrow slit pores. These IAST selectivities are some of the highest values for carbon materials reported in the literature so far and the highest IAST selectivities for as‐prepared, non‐post‐treated carbon ever. [ABSTRACT FROM AUTHOR]

High‐temperature co‐electrolysis shows comparable performance to steam electrolysis. Current densities above 1 A cm−2 can be reached between 700 °C and 800 °C. Tailor‐made syngas is produced, mainly determined by the reactant ratio. The experimental results are supported by modeling. Durability tests with cathode‐supported cells show increased voltage degradation rates during electrolysis compared to fuel cell operation. Nickel depletion is found to be the main cause. [ABSTRACT FROM AUTHOR]

Lead‐oxide stoichiometry of lead‐zirconate‐titanate (PZT) ceramics and multilayer actuators is a critical issue for fabrication and performance. During sintering, the high vapor pressure and the corresponding volatility of lead oxide (PbO) require a careful design of sintering setup and parameters, as both may significantly impact on the PbO content in ceramics and devices. In order to investigate the effects of PbO stoichiometry, PZT compositions with different PbO contents have been synthesized and were sintered under varying temperature conditions and sintering setups. Structure and microstructure of the material was characterized using X‐ray diffraction and scanning electron microscopy (SEM). Dielectric properties and high field strain behavior were analyzed with respect to their relation to PbO content and grain size. Corresponding experiments with multilayer actuators were carried out, whereby the PbO content was varied by controlling the sintering atmosphere. The results indicate that there is a pronounced correlation between PbO content, structure and high field strain in both, PZT ceramics, and multilayer actuators. [ABSTRACT FROM AUTHOR]

Power-to-X concepts promise a reduction of greenhouse gas emissions simultaneously guaranteeing a safe energy supply even at high share of renewable power generation, thus becoming a cornerstone of a sustainable energy system. Power-to-syngas, that is, the electrochemical conversion of steam and carbon dioxide with the use of renewably generated electricity to syngas for the production of synfuels and high-value chemicals, offers an efficient technology to couple different energy-intense sectors, such as 'traffic and transportation' and 'chemical industry'. Syngas produced by co-electrolysis can thus be regarded as a key-enabling step for a transition of the energy system, which offers additionally features of CO2-valorization and closed carbon cycles. Here, we discuss advantages and current limitations of low- and high-temperature co-electrolysis. Advances in both fundamental understanding of the basic reaction schemes and stable high-performance materials are essential to further promote co-electrolysis. [ABSTRACT FROM AUTHOR]

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Nanocrystalline LiTi2(PO4)3/C has been synthesized by employing a solvothermal process in which oxalic acid was used as a solubilizer for the titanium source, a surfactant, and a carbon source. Additionally, Pechini's sol-gel-based method was also used as the synthesis method for comparison. LiTi2(PO4)3/C prepared by using a solvothermal route showed a homogenous particle size with spindle-like microstructures formed from self-assembled nanosized-platelets, whereas preparation by the sol-gel process resulted in agglomerated powders with irregular morphology and particle size. The different morphologies of LiTi2(PO4)3/C prepared in the two synthesis methods tend to form different electrode layer structures, which results in remarkable differences in their electrochemical properties. In particular, the solvothermally synthesized LiTi2(PO4)3/C composite exhibits superior high-rate-discharge capability and cycling stability. A capacity of approximately 97.7 % of the initial capacity was maintained for the solvothermal sample after 500 cycles at 5 C. [ABSTRACT FROM AUTHOR]

Solar cell in combination with a secondary battery is a straightforward power supply solution for portable electronics. When used indoors or outdoors under sufficient illumination conditions the combination is attractive to realize self-sustained devices or extend off-grid operation time. However, only little fraction of widely spread portable devices worldwide are equipped with PV energy harvesters. Besides low-average power, combination of discrete PV module and battery is bulky for extreme demands in modern portable electronics. Integration of thin-film solar cell with a thin-film storage cell in a monolithic, customizable module is a viable option. The low level cell-to-cell integration is possible with thin-film silicon multi-junction solar cells providing sufficient voltage to charge Li-ion storage cell. In this work, we focus on the development of triple-junction thin-film silicon solar cells for monolithic integration with lithium ion storage cells. We show that with appropriate voltage matching a triple junction thin-film silicon solar cell provides efficient charging for lab-scale Li-ion storage cell under a range of illumination intensities. Maximum solar energy-to-battery charging efficiency of 8.8% was obtained. [ABSTRACT FROM AUTHOR]

Aprotic lithium-oxygen (Li-O2) batteries have attracted considerable attention in recent years owing to their outstanding theoretical energy density. A major challenge is their poor reversibility caused by degradation reactions, which mainly occur during battery charge and are still poorly understood. Herein, we show that singlet oxygen (1Δg) is formed upon Li2O2 oxidation at potentials above 3.5 V. Singlet oxygen was detected through a reaction with a spin trap to form a stable radical that was observed by time- and voltage-resolved in operando EPR spectroscopy in a purpose-built spectroelectrochemical cell. According to our estimate, a lower limit of approximately 0.5 % of the evolved oxygen is singlet oxygen. The occurrence of highly reactive singlet oxygen might be the long-overlooked missing link in the understanding of the electrolyte degradation and carbon corrosion reactions that occur during the charging of Li-O2 cells. [ABSTRACT FROM AUTHOR]

The influence of heat treatment in lead zirconate titanate Pb( Zr, Ti) O3 ( PZT) ferroelectrics on the domain structure and strain behavior has been investigated. Temperature-induced changes in the domain configuration, for example, appearance of nanodomains within microdomains, were observed by in situ hot-stage transmission electron microscopy. During the transient post annealing state the strain behavior under electric field differed from that of the nonheat-treated ferroelectrics. Directly after cooling the difference was most pronounced and decreased as a function of time. The enhanced response to an electric field of 4 kV/mm resulted in qualitatively different effects on strain for PZT from the tetragonal side and from the rhombohedral side of the morphotropic phase boundary. [ABSTRACT FROM AUTHOR]

Keywords: metal-air batteries; iron electrodes; hydrogen evolution reaction; in situ gas chromatography; quantitative analysis EN metal-air batteries iron electrodes hydrogen evolution reaction in situ gas chromatography quantitative analysis 1 1 1 05/10/22 20220501 NES 220501 B The Front Cover b illustrates the hydrogen evolution on carbonyl iron electrodes with the latter being a resource-efficient option to store renewable electricity for stationary applications. Metal-air batteries, iron electrodes, hydrogen evolution reaction, in situ gas chromatography, quantitative analysis Cover Picture: In Situ Hydrogen Evolution Monitoring During the Electrochemical Formation and Cycling of Pressed-Plate Carbonyl Iron Electrodes in Alkaline Electrolyte (Batteries & Supercaps 5/2022). [Extracted from the article]

Five new compounds, [Rb(crown-6)]3[C60] ( 1), [Rb(crown-6)]6[C60]2(C3H7NO)2(C4H8O)2 ( 2), [Rb(benzocrown-6)]6[C60]2(C2H8N2)5 ( 3), [Cs(benzocrown-6)]3C60(C2H8N2)2 ( 4), and [Cs3(benzocrown-6)5]C60(C2H8N2)(4.5+x) ( 5) were synthesized and characterized by single-crystal X-ray structure determination. All compounds contain discrete C60 anions, which are ordered in 1, 2, and 4, where direct cation-anion contacts occur. The unit cells of 1 and 2 contain two independent fullerides, which coordinate to the rubidium atoms either of two or of four [Rb(crown-6)] units. Owing to the presence of differently coordinated fullerene units in compounds 1 and 2, a possible disproportionation of C603- into C602- and C604- anions is discussed. In 3 and 4 the C60 anions are coordinated by three Rb and Cs atoms, respectively. In all compounds the average charge of the anion is -3. Magnetic data reveal a doublet spin state for 3. The EPR spectra are discussed for compounds 3 and 5. The role of a dynamic Jahn-Teller distortion is discussed, and we report the first IR spectroscopic data of fullerene trianions, which have been obtained in solution. [ABSTRACT FROM AUTHOR]

Perovskite-type LaVO2.78N0.10 powder was synthesized by thermal ammonolysis of the oxide precursor LaVO4. By X-ray, neutron, and electron diffraction an orthorhombic crystal structure with space group Pnma was identified. XANES spectra showed that the oxidation state of vanadium changes from 5+ in LaVO4 to approximately 3+ in LaVO2.78N0.10. The temperature dependence of the electrical conductivity revealed an Arrhenius-type behavior with an activation energy of 0.103 eV in the temperature range of 119-302 K indicating that the conduction process is thermally activated band transition. Based on the positive Seebeck coefficient, holes were identified as the dominant charge carriers in the temperature range of 100-302 K. Both the Seebeck coefficient and the thermal conductivity showed an anomaly at 138 K, which is attributed to the Néel temperature for antiferromagnetic ordering according to magnetic susceptibility measurements. [ABSTRACT FROM AUTHOR]

The electrocatalytical process at the air cathode in novel silicon-air batteries using the room-temperature ionic liquid hydrophilic 1-ethyl-3-methylimidazolium oligofluorohydrogenate [EMI ⋅2.3 HF ⋅F] as electrolyte and highly doped silicon wafers as anodes is investigated by electrochemical means, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) spectroscopy. The results obtained by XPS and EPR provide a model to describe the limited discharge capacity by means of a mechanism of air-electrode deactivation. In that respect, upon discharge the silicon-air battery′s cathode is not only blocked by silicon oxide reduction products, but also experiences a major modification in the MnO2 catalyst nature. The proposed modification of the MnO2 catalyst by means of a MnF2 surface layer greatly impacts the Si-air performance and describes a mechanism relevant for other metal-air batteries, such as the lithium-air. Moreover, the ability for this deactivation layer to form is greatly impacted by water in the electrolyte. [ABSTRACT FROM AUTHOR]