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Halide perovskite materials have gained enormous attention for their semiconducting properties, higher power conversion efficiency and potential applications in a wide range of fields of study, along with their two key limitations: stability and toxicity. Despite great progress made on halide perovskites and many promising research developments, the issues of stability and toxicity have not been fully resolved. Therefore, the coordination engineering of a new framework to obtain alternative new halide perovskite materials and a fundamental understanding of the coordination chemistry and electronic interactions forming the structure of these newly engineered halide perovskite materials are possible ways to overcome the issues related to both stability and toxicity. In this review, we comprehensively review the current development of halide perovskite families, both lead halide perovskites and lead-free halide perovskites, followed by the coordination engineering of the new frameworks to engineer new halide perovskite materials. All concerns regarding the fundamental ideas of coordination chemistry and electronic interactions are vital in forming halide perovskite structures and thus form the main aim of this review. We also discuss recent potential energy applications beyond photovoltaics and thus answer an essential and open question, 'what could happen in the future of halide perovskites?' in order to excite commercial enterprises and research institutions again as well as to motivate new predictions on the future continuity of this field. [ABSTRACT FROM AUTHOR]

The quality of the SEI layer was improved through the synergistic effect of fluoroethylene carbonate (FEC) and lithium difluorophosphate (LiPF) dual additives. [Display omitted] • Role of dual additives (FEC and LiPF) on the electrolyte reactivity with Li metal anodes is analyzed. • Synergistic effects of dual additives on SEI formation mechanisms are explored. • Atomic charges are used to predict the representative F 1s XPS and confirmed experimentally identified SEI components. • Constructive suggestions have been proposed for improving SEI quality. Improving the quality of the solid-electrolyte interphase (SEI) layer is highly imperative to stabilize the Li-metal anodes for the practical application of high-energy–density batteries. However, controllably managing the formation of robust SEI layers on the anode is challenging in state-of-the-art electrolytes. Herein, we discuss the role of dual additives fluoroethylene carbonate (FEC) and lithium difluorophosphate (LiPO 2 F 2 , LiPF) within the commercial electrolyte mixture (LiPF 6 /EC/DEC) considering their reactivity with Li metal anodes using density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations. Synergistic effects of dual additives on SEI formation mechanisms are explored systematically by invoking different electrolyte mixtures including pure electrolyte (LP47), mono-additive (LP47/FEC and LP47/LiPF), and dual additives (LP47/FEC/LiPF). The present work suggests that the addition of dual additives accelerates the reduction of salt and additives while increasing the formation of a LiF-rich SEI layer. In addition, calculated atomic charges are applied to predict the representative F 1s X-ray photoelectron (XPS) signal, and our results agree well with the experimentally identified SEI components. The nature of carbon and oxygen-containing groups resulting from the electrolyte decompositions at the anode surface is also analyzed. We find that the presence of dual additives inhibits undesirable solvent degradation in the respective mixtures, which effectively restricts the hazardous side products at the electrolyte-anode interface and improves SEI layer quality. [ABSTRACT FROM AUTHOR]

Abstract: CO poisoning is a major issue for proton-exchange membrane fuel cells (PEMFCs) when reformate gas is used as a fuel, especially at low temperatures (<80 °C). The performance of a PEMFC is investigated when subject to CO poisoning under different operation conditions and a simplified model is hereby proposed. It is found that even when the a CO-tolerant material like platinum–ruthenium (Pt–Ru) is used as the anode catalyst, the cell loses approximately 40% of its current density within 40 min with hydrogen fuel containing 25 ppm CO. By applying 5% air bleeding, the cell output current can be restored to 90% within 10 min, even at high CO concentrations (200 ppm). However, excessive air bleeding (>10% air) also reduces the cell output power. Based on impedance measurements, CO poisoning can strongly increase the charge transfer resistance without affecting the cell internal resistance. The stability test for 300 h using 200 ppm CO and 5% air bleeding shows that the cell power output can remain stable with the overall degradation less than 2%. From the viewpoints of system design and operation, air bleeding offers a stable power output and allows for a simpler, smaller, and cheaper reformer. [Copyright &y& Elsevier]

Abstract: The microstructural modifications associated with the lowering of hydrophilic/hydrophobic phase separation can reduce the molecular permeation in an ionomer without compensating the ionic conductivity significantly. This idea has been investigated by selecting poly (vinyl alcohol) PVA as the polymer matrix of proton exchange membranes. 4-Formyl-1,3-benzenedisulfonic acid disodium salt (DSDSBA) molecules, with two protogenic groups tethered to the rigid aromatic ring are introduced to the polymer chains as ion carriers. With a view to improve the morphological stability, glutaraldehyde is used as the cross-linking agent. The molecular chemistry such as flexible backbone, short and rigid side chains and dense acid functionalities improved the selective proton conduction through the membranes. The ionomers show up to eight times selectivity as that of Nafion for protons over methanol. The XRD, DSC and FTIR results are employed to establish the microstructural features of hydrated membranes. Large sorption of nonfreezing water is identified as the main reason for the attractive DMFC membrane characteristics of the prepared membranes. A detailed analysis of the state of water in the prepared membranes reveals that well connected system of narrow water channels allowed for low methanol permeation along with high mobility of protonic charge carriers. [Copyright &y& Elsevier]

Abstract: In this study, a novel mesoporous carbon-encapsulated NiO nanocomposite is proposed and demonstrated for Li-ion battery negative electrode. The nanostructure of the electrode composes of an ordered mesoporous CMK-3 as a 3D nanostructured current collector with micorporous channels for Li+ transportation. In addition, exclusive formation of NiO nanoparticles in the confined space of the ordered mesoporous carbon is achieved using the hydrophobic encapsulation route. The half-cell assembled with the synthesized NiO/CMK-3 nanocomposite is able to deliver a high charge capacity of 812mAhg−1 at the first cycle at a C-rate of 1000mAg−1 and retained throughout the test with only 0.236% decay per cycle. Even the C-rate as high as 3200mAg−1, a charge capacity of 808mAhg−1 contributed by the NiO nanoparticles in CMK-Ni is obtained, which shows excellent rate capability for NiO with utilization close to 100%. The result suggests fast kinetics of conversion reaction for NiO with Li+. It also indicates the blockage of the pore channels by NiO nanoparticles does not take place in the synthesized NiO/CMK-3. [Copyright &y& Elsevier]

Abstract: In the present work, the dynamic behavior of a PEM fuel cell under CO-poisoning and the effects of air bleeding on the recovery ratio are reported. Pt–Ru catalyst is used as the anode in a single cell and the hydrogen is pre-mixed with 53ppm of CO as the fuel. The result indicates that even using a CO-tolerant catalyst, CO-poisoning cannot be avoided with the operating conditions in our study. About 80% of the output current is lost within 20min. Upon anode air bleeding with 5% air, 90% of the current is recovered within 1min. Higher air bleeding ratio only results in minor improvement of the cell performance. We have developed a transient model to estimate the current reduction due to CO-poisoning and to evaluate the amount of air bleeding needed for a given recovery ratio. A long-term durability test has also been conducted using simulated reformatted gas, in which 1% O2 is injected into the fuel stream. After more than 3000h, the cell voltage degradation is less than 3%. [Copyright &y& Elsevier]

Abstract: The synthesis of rod-like LiFePO4/C cathodes using template-free reverse micelle process is reported for high performance lithium batteries. We have demonstrated that the size of the primary particles could be controlled based on sintering temperature and sintering time and size of the large aggregates is adjustable based on the carbon content of the sample. Thermogravimetry and differential thermal analysis have been used to propose a possible mechanism for the formation rod-like LiFePO4/C cathode material. X-ray diffraction, scanning electron microscopy, impedance spectroscopy and charge–discharge measurements have been used to characterize the material. Electrochemical performance of rod-like LiFePO4/C cathode material offers higher initial capacity and excellent rate capability than that obtained by loose porous LiFePO4/C material due to unique rod-like composite material formed by primary nanoparticles. Hence, it can be suggested that that the rod-like nanostructured morphology improves structural stability, lithium ion diffusion and electronic conductivity of the LiFePO4/C composite material. The template-free reverse micelle process for the synthesis of the rod-like LiFePO4/C cathode material opens up a new route to synthesize lithium transition metal oxides with controlled morphologies for applications in high power lithium batteries. [Copyright &y& Elsevier]

Abstract: Morphological control of the nanostructured α-Ni(OH)2 is achievable via self-assembly of sodium dodecyl sulfate (SDS) as templates accompanied with microwave-assisted homogeneous alkalization process. The synthesized α-Ni(OH)2 can be 2-D hexagonal nano-sheets, macroporous micro-spheres or irregular-shaped platelets, depending on the SDS concentration. Further, the interlayer spacing of the synthesized α-Ni(OH)2 crystalline was determined to be 2.47nm, indicating the intercalation of DS− anions between brucite layers. The results explain the morphological change of the synthesized α-Ni(OH)2 with SDS concentration, which provides a way to morphological control of metal hydroxides. The corresponding electrochemical properties for the α-Ni(OH)2 synthesized with and without SDS are characterized as well, showing the advantages of the 2-D hexagonal nano-sheets. [Copyright &y& Elsevier]

Abstract: Variation of electronic structure for chemically delithiated LiCoO2 was investigated by X-ray absorption spectroscopy (XAS) at Co L-edge, K-edge and O K-edge. The commercial LiCoO2 powders were de-intercalated by an oxidizing agent, Na2S2O8, in an aqueous solution. The soft XAS was performed at total electron yield as well as fluorescence modes. It was found that the changes in the spectral feature obtained from total electron yield mode are different from that obtained from fluorescence mode at the oxygen K-edge. The electronic transition from oxygen ls state to 2p hole state (threshold energy) decreases at the surface region but not in the bulk. The shoulder absorption peak at the energy higher than the threshold energy contributed to the higher oxidation state of the oxygen site appears at total electron yield mode but does not appear at fluorescence mode, indicating the oxidation state of oxygen and the electronic transitions on the surface and in the bulk of the delithiated compounds are different. It implies that the chemically delithiated process takes place inhomogeneously and starts from the surface of the Li x CoO2 compounds. [Copyright &y& Elsevier]

Abstract: The structural changes of pristine and ZrO2-coated LiMn0.5Ni0.5O2 cathode materials were investigated by using in situ X-ray diffraction (XRD) during charging process. An obviously solid solution phase transition from a hexagonal structure (H1) to another hexagonal structure (H2) was observed during the charging process at a constant current of 0.3mA in the potential range of 2.5–5.7V. The second hexagonal structure has a shorter a-axis and a longer c-axis before the crystal collapse. Before the structure collapses the c-axis length increases to maximum and then significantly decreases to 14.1Å. The c-axis length of the pristine and ZrO2-coated LiMn0.5Ni0.5O2 increases to the maximum at the charge capacity of 119.2 and 180.9mAhg−1, respectively. It can be concluded that the ZrO2 coating can strongly stabilize the crystal structure of the LiMn0.5Ni0.5O2 compound from the comparison of the lattice parameter variations between the pristine and the ZrO2-coated LiMn0.5Ni0.5O2 compounds upon charge. The potential fluctuation resulting from the decomposition of electrolytes starts at the charge capacity of around 200 and 260mAhg−1 for the pristine and ZrO2-coated LiMn0.5Ni0.5O2, respectively. It suggests that the ZrO2 coating layer can impede the reaction between the cathode material and electrolyte. [Copyright &y& Elsevier]

An accelerated sol–gel process with water/vapor management was developed here to synthesize SiO2–P2O5 glass electrolytes for shortening the gelation time and enhancing their proton conductivities. The gelation time needed is shortened from 1 to 6 months in the Wang et al.’s report [Mater. Lett. 42 (2000) 225] to about 3 days successfully in the developed process. The gelation reactions in the sol–gel process for the synthesis of SiO2–P2O5 glass electrolytes were investigated by in situ FTIR spectroscopy. Types of water involving free/hydrogen bonded/strong hydrogen bonded water and hydroxyl group in the synthesized SiO2–P2O5 glass electrolytes were determined by TGA and in situ FTIR. A SiO2–P2O5 glass electrolyte with a methanol permeability of 2.1 × 10-9 cm2/s and high proton conductivity (9.45 × 10-3 S/cm) was obtained by the developed process. [Copyright &y& Elsevier]

The electrochemical lithium-ion extraction/insertion properties of a spinel LiAl0.15Mn1.85O4 material were studied. Cyclic voltammetry shows two-step reactions for lithium-ion extraction/insertion at its 4 V plateau. Synchrotron in situ X-ray diffraction studies show that lithium ions are extracted and inserted from the LiAl0.15Mn1.85O4 material, respectively, from two to three different environments. The different environments may be due to different Li–Li interactions and/or different intensities of interactions with the nearest neighbors in the spinel LiAl0.15Mn1.85O4 material frame work. From the Mn absorption edge measurements as a function of potential, during lithium extraction, it can be suggested that the charge transfer rate is faster than that of structural transformations. However, during lithium insertion, the rate of both charge transfer and structural transformations are more or less similar. [Copyright &y& Elsevier]

Pt/Nafion® and Pd/Nafion® electrodes were prepared by impregnation–reduction methods in detecting hydrogen. For improving their anti-aging abilities, polypyrrole (PPy) films were chemically deposited onto the metallized electrodes. After continuously aging tests for 48 h, the sensitivities of the Pt/Nafion® and the PPy-modified Pt/Nafion® electrodes decrease by 68 and 32%, respectively, but the accompanying sacrifice is the loss in sensitivity from 0.0744 to 0.0261 μA/ppm. Similarly, the sensitivities of the Pd/Nafion® and the PPy-modified Pd/Nafion® electrodes decrease by 84 and 68%, respectively, accompanying with the sacrifice of loss in sensitivity from 0.0519 to 0.0262 μA/ppm. [Copyright &y& Elsevier]

Pt/C/Nafion® composite electrodes prepared by a hot-pressed method were modified by chromium (Cr) for sensing hydrogen and oxygen in this study. The results indicate that the sensitivities of the Cr-modified electrodes in sensing hydrogen and oxygen rise markedly from 0.716 to 0.771 and from 0.414 to 0.533 μA per ppm, respectively, and the response and the recovery times on the Cr-modified electrode are shortened. Meanwhile, the Cr-modified Pt/C/Nafion® electrode can depress the aging in continuously sensing oxygen for 250 h. After aging, the sensitivities of the Pt/C/Nafion® electrode and the Cr-modified Pt/C/Nafion® electrode decrease by 81 and 65%, respectively. Generally, both the response and the recovery times decrease significantly with increasing gases concentrations. A sensing model was also proposed to illustrate the sensing phenomenon. [Copyright &y& Elsevier]

Effects of surfactants on codeposition of PTFE particles with electroless Ni-P coating were investigated in this study. Dependence of the deposition rate of Ni-P matrix and PTFE particles on the surfactant concentration and the PTFE loading were reported. It indicates that the deposition behaviors of the Ni-P matrix and PTFE particles depends strongly on the weak adsorption of PTFE particles on the substrate, the reactivity of the surfactants (strong adsorption) and the surface coverage of the surfactant on the substrate. A theoretical model was proposed to provide a more deep insight into the codeposition behaviors. [Copyright &y& Elsevier]

The surface-enhanced Raman spectroscopy (SERS) of polypyrrole (PPy) can be obtained by roughening the Au substrate with electrochemical oxidation–reduction cycle (ORC) before PPy deposition. The optimum condition for obtaining SERS effect is based on the strongest peak of C&z.dbnd6;C backbone stretching of PPy located at ca. 1600 cm−1 shown in SERS. The optimum preparation conditions are as follows. Cathodic and anodic vertex potentials are −300 and 1200 mV vs. SCE, respectively. Delays at cathodic and anodic vertex potentials are 10 and 2 s, respectively. Cathodic and anodic scan rates are 500 and 1000 mV s−1, respectively. The ORC cycle is 25 times. Also, the result indicates that the SERS effect decreases with increasing the charge passed for PPy deposition. [Copyright &y& Elsevier]

Over the past few years, halide solid‐state electrolytes (HSSEs) have attracted the attention of researchers, and many reports about HSSEs have been published. Their wide electrochemical window (ECW) and a quite good compatibility with the popular oxide cathode materials make them attractive for practical applications. As a result, HSSEs are exciting candidates for the future generation of all‐solid‐state Li batteries (ASSLBs). In recent years, noticeable efforts have been made to develop novel HSSEs and utilize them in ASSLBs. Herein, a comprehensive update on the progress of HSSEs development and their application in ASSLBs is provided. First, a brief summary of the conductivity of HSSEs and potential synthesis approaches is provided. Next, the moisture and phase stabilities of HSSEs are reviewed separately, and the techniques proposed in the recently published reports to achieve sufficient stabilities are summarized. In addition, the electrochemical stabilities of HSSEs with Li metal anode and oxide cathode materials, from experimental and theoretical points of view, are provided in parallel. Furthermore, the application and progress of HSSEs in high‐voltage ASSLBs are discussed. Finally, new research directions are suggested for the development of scalable HSSEs‐based ASSLBs. [ABSTRACT FROM AUTHOR]

Single-atom catalysts exhibit immense potential across diverse reactions, yet their synthesis and stability in acidic environments pose significant challenges. Herein, we introduce a facile one-step hydrothermal approach to fabricate Ru single-atom alloy catalysts (Ru SAAC) through the reaction of Ru and Ti precursors, followed by annealing in an argon atmosphere. Analysis via extended X-ray absorption fine structure spectroscopy and aberration-corrected scanning transmission electron microscopy confirms the atomically dispersed Ru alloy catalyst anchored on a TiO 2 support. Remarkably, Ru SAAC demonstrates exceptional electrocatalytic performance in the iodide oxidation reaction (IOR), achieving a benchmark current density of 10 mA/cm2 at a mere voltage of 0.64 V in acidic conditions within a three-electrode electrolyzer setup. Surpassing nanoscale Ru/TiO 2 and RuO 2 /TiO 2 counterparts, Ru SAAC exhibits the highest voltage efficiency (84.4%), lowest Tafel slope (36 mV/dec), and lowest overpotential (100 mV) under identical experimental conditions. This method enables facile control over Ru morphology. It enhances the kinetics and thermodynamic favorability of Ru SAAC in acidic media, opening avenues for synthesizing diverse transition metal-based single-alloy catalysts for varied applications. [Display omitted] • A simple one-step hydrothermal method to fabricate Ru single-atom alloy catalysts. • Achieving a low potential of 0.64 V at 10 mA/cm2, outperforming other Ru/TiO₂ catalysts. • Energy-saving iodide oxidation reaction favorable for coupling hydrogen production. • It gives highest voltage efficiency (84.4%), lowest Tafel slope (36 mV/dec), lowest overpotential. • Method offers easy control over Ru morphology, enhancing kinetics and stability in acidic media. [ABSTRACT FROM AUTHOR]

State‐of‐the‐art ternary layered oxide cathode active materials in Li‐ion batteries (LIBs) consist of polycrystalline (PC), i.e., micron‐sized secondary particles, which in turn consist of numerous nanosized primary particles. Recent approaches to develop single crystals (SCs), i.e., single and separated micron‐sized primary particles, appear promising in terms of cycle life given their mechanical stability. However, a direct and systematic ("fair") comparison of SC with PC in LIB cell application remains a challenge due to both differences on material level and state‐of‐charge (SoC), as SCs typically have slightly lower delithiation capacities/Li+ extraction ratios. In this work, PC and SC Li[Ni0.8Mn0.1Co0.1]O2 (NMC811) are synthesized with comparable bulk and surface characteristics from identical self‐synthesized precursors. Indeed, the cycle life of SCs is not only superior, when conventionally charged to equal upper cutoff voltage (UCV), as shown in NMC||Li and NMC||graphite cells, but also after adjusting UCVs to similar SoCs, where bigger SCs counterintuitively have even a better rate performance and cycle life. [ABSTRACT FROM AUTHOR]

The solid electrolyte is anticipated to prevent lithium dendrite formation. However, preventing interface reactions and the development of undesirable lithium metal deposition during cycling are difficult and remain unresolved. Here, to comprehend these occurrences better, this study reports an alloy formation strategy for enhanced interface stability by incorporating antimony (Sb) in the lithium argyrodite solid electrolyte Li6PS5Cl (LPSC‐P) to form Li–Sb alloy. The Li–Sb alloy emergence at the anodic interface is crucial in facilitating uniform lithium deposition, resulting in excellent long‐term stability, and achieving the highest critical current density of 14.5 mA cm−2 (among the reported sulfide solid electrolytes) without lithium dendrite penetration. Furthermore, Li–Sb alloy formation maintain interfacial contact, even, after several plating and stripping. The Li–Sb alloy formation is confirmed by XRD, Raman, and XPS. The work demonstrates the prospect of utilizing alloy‐forming electrolytes for advanced solid‐state batteries. [ABSTRACT FROM AUTHOR]

• Uniformly distributed Au-nanoflowers on Si-wafer as support for capture surface. • LSPR coupling between Au-nanoflowers helps improve detection sensitivity. • SERS mapping reduces spot-to-spot variation in quantitative SERS. • Incubating capture surface in microwell plates significantly reduces positive error. Reliability of a method for cancer detection is a key issue. It is because of fear for false positive and false negative results that no tumor marker has been recommended for cancer screening test yet. Surface-enhanced Raman scattering (SERS) is highly sensitive and a promising technique for cancer detection. However, huge spot-to-spot variation in SERS signal and false positive result in SERS-based immunoassay degrade its reliability. In this work, we designed gold nanoflower (AuNF)-based SERS method for detection of pancreatic cancer marker MUC4 and demonstrated approaches to improve reliability of the method. We employed Raman mapping over a large area of the substrate to minimize effect of spot-to-spot variation. Furthermore, the use of microwell plate for incubation of capture substrate minimized blank value significantly. The designed method is sensitive enough to detect MUC4 down to 0.1 ng mL−1. The use of AuNFs to construct both ERL and capture surface has contributed to the improved detection sensitivity. [ABSTRACT FROM AUTHOR]

The utilization of liquid electrolytes (LEs) concerns inevitable dendrite growth and safety issues. In contrast, solid polymer electrolytes suffer from unsettled low ionic conductivity and interfacial impedance issues. The intermediary gel polymer electrolytes (GPEs) improve safety by incorporating a sturdy polymer matrix and ionic conductivity as an advantage of percolating LEs responsible for gelation. The overall stability and compatibility of GPEs with different electrode materials depend on the polymers, plasticizers, and precursors utilized. No single polymer has a wide energy gap to exhibit stability against Li metal anodes and oxidative stability against high‐voltage cathodes. Thereafter, symmetric GPEs (SGPEs) possess limitations while simultaneously satisfying the two electrode requirements, which hinders their practical applications. Asymmetric GPEs (ASGPEs) generally comprise a bilayer or gradient structure, wherein the side contacting the cathode is modified to promote oxidative stability for a stable cathode electrolyte interface (CEI). The corresponding side in contact with the anode is modified to be mechanically and chemically compatible with dendritic lithium. Overall, asymmetric structural engineering enables electrode compatibility while maintaining the physical competency of GPEs. Herein, the focus is to summarize the current transition from SGPEs to asymmetric ones, which promotes multifunctionality while overcoming specific constraints associated with the electrodes. [ABSTRACT FROM AUTHOR]

Selecting electrolytes is critical before assembling a cell to achieve good performance in a Li metal battery. An Ag-coated groove with hill and valley features is prepared by magnetron sputtering on a 3D structure array pattern laying on a commercial Cu foil to act as a platform to evaluate liquid electrolytes in Li//Cu half-cell configuration. The 3D Ag-coated groove with hill and valley feature provides the capability to determine the uniformity in terms of throwing power (TP) of various electrolytes, which is correlated with their electrochemical performance. The increase in TP value after applying fluoroethylene carbonate (FEC) (−3.59%) and tris(trimethylsilyl) phosphite (TMSP) (−49.60%) as an additive is in contrast to the TP value of the pristine electrolyte w/o additive (−66.84%), which is in line with the higher average coulombic efficiency achieved (95.39% for FEC and 94.87% for TMSP) compared to LiPF 6 alone (91.89%). Moreover, the FEC-contained electrolyte achieves the lowest value of resistance (18.76 Ω and 10.92 Ω) and average surface roughness Ra (24.8 and 22.4 nm) on hill and valley, respectively, among the investigated electrolytes. Applying the design of an Ag-coated groove gives significant insight into how a platform can be built to comply with the effort in screening the good options for liquid electrolytes in Li metal battery application. [Display omitted] • Photolithography and magnetron sputtering are used for 3D structure modification on Cu foil. • An electrolyte evaluating platform is designed based on the throwing power of hill and valley of 3D Ag-coated groove. • AFM and EIS characterizations are conducted on hills and valleys and then correlated with the throwing power capability. [ABSTRACT FROM AUTHOR]

Solid‐state batteries (SSBs) with a Li7La3Zr2O12 (LLZO) garnet electrolyte are attracting much attention as robust and safe alternative to conventional lithium‐ion batteries. Technical challenges in the practical implementation of garnet SSBs are related to the need for high‐temperature sintering, which often leads to undesirable chemical reactions with the cathode material. While these reactions are well understood for composite cathodes, very little is known about similar processes between cathode and separator during battery fabrication. This work focuses on understanding the processes between the composite LiCoO2‐LLZO cathode and the LLZO separator and how they affect the battery performance. The extensive diffusion of Co‐ions within LLZO, which leads to the often‐observed LLZO darkening, is shown to have a significant impact on ionic conductivity, electronic conductivity, and dendrite stability of the separator. Experimental data coupled with large‐scale molecular dynamics simulations uncover the diffusion mechanism for Co‐ions and identify secondary phases that form during these interactions. In addition to extensive Co‐ion diffusion within the grains, a non‐uniform segregation of Co‐ions at grain boundaries is found leading to the formation of three distinct Co‐containing phases. This work offers a general approach to studying the fundamental ion diffusion processes that occur during the fabrication of oxide SSBs. [ABSTRACT FROM AUTHOR]

Splitting water for hydrogen production using light, or electrical energy, is the most developed 'green technique'. For increasing efficiency in hydrogen production, currently, the most exciting and thriving strategies are focused on efficient and inexpensive catalysts. Here, we report an innovative idea for efficient hydrogen evolution reaction (HER) utilizing plasmon-activated liquid water with reduced hydrogen-bonded structure by hot electron transfer. This strategy is effective for all HERs in acidic, basic and neutral systems, photocatalytic system with a g-C3N4 (graphite carbon nitride) electrode, as well as in an inert system with an ITO (indium tin oxide) electrode. Compared to deionized water, the efficiency of HER increases by 48% based on activated water ex situ on a Pt electrode. Increase in energy efficiency from activated water is 18% at a specific current yield of −20 mA in situ on a nanoscale-granulated Au electrode. Moreover, the onset potential of −0.023 V vs RHE was very close to the thermodynamic potential of the HER (0 V). The measured current density at the corresponding overpotential for HER in an acidic system was higher than any data previously reported in the literature. This approach establishes a new vista in clean green energy production. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries, simply known as lithium batteries, are distinct among high energy density charge-storage devices. The power delivery of batteries depends upon the electrochemical performances and the stability of the electrode, electrolytes and their interface. Interfacial phenomena of the electrode/electrolyte involve lithium dendrite formation, electrolyte degradation and gas evolution, and a semi-solid protective layer formation at the electrode–electrolyte interface, also known as the solid–electrolyte interface (SEI). The SEI protects electrodes from further exfoliation or corrosion and suppresses lithium dendrite formation, which are crucial needs for enhancing the cell performance. This review covers the compositional, structural and morphological aspects of SEI, both artificially and naturally formed, and metallic dendrites using in situ/in operando cells and various in situ analytical tools. Critical challenges and the historical legacy in the development of in situ/in operando electrochemical cells with some reports on state-of-the-art progress are particularly highlighted. The present compilation pinpoints the emerging research opportunities in advancing this field and concludes on the future directions and strategies for in situ/in operando analysis. [ABSTRACT FROM AUTHOR]

The article "Systematic 'Apple-to-Apple' Comparison of Single-Crystal and Polycrystalline Ni-Rich Cathode Active Materials" in the journal "Small Structures" compares the cycle life of conventional polycrystal (PC)-based Li[NixMnyCoz]O2 (NMC) with single crystal (SC)-based NMC cathodes. Both cathode types are synthesized from identical precursors, with the SC-NMC showing superior cycle life despite requiring a higher cutoff voltage. The research was conducted by a team of authors including Johannes Kasnatscheew, Marco Joes Lüther, Shi-Kai Jiang, Martin Alexander Lange, Julius Buchmann, Aurora Gómez Martín, Richard Schmuch, Tobias Placke, Bing Joe Hwang, and Martin Winter. [Extracted from the article]

Sulfide SSEs (solid-state electrolytes) with high ionic conductivity are attractive for developing high-safety all-solid-state batteries (ASSBs). However, the poor chemical stability of sulfide SSEs toward moisture is a significant problem. Though the decomposition products when exposed to moisture and a possible property recovery by heat treatment are reported, the evolution of surface species in related to moisture exposure and to heat treatment is not clearly identified. This study applies in situ DRIFTS (diffuse reflectance infrared Fourier-transformed spectroscopy) analysis to examine the evolution of the surface species over pristine Li 6 PS 5 Cl (LPSC), during moisture exposure, and during heat treatment, complementary with tools like XRD, Raman, etc. The observed surface impurities over pristine LPSC include LiCl·H 2 O, LiOH·H 2 O, S 3 P-SH, PS 4-x O x , SO x and carbonate species. Moisture exposure leads to increasing accumulation of these species over LPSC and evolving hydrogen sulfide. A stepwise heat treatment up to 480 °C illustrates the sequential removal of hydrated water, the decomposition of carbonate, LiOH, and PS 4-x O x , leaving species like LiCl, Li 2 O, and PO 4 on the surface. The EIS results shows a gradual increase in the ionic conductivity of LPSC with increasing heating temperature, mainly owing to the decreasing surface layer impedance. This strongly suggests that the surface species govern the properties of LPSC. When using the pristine LPSC after heat treatment at 480 °C, the Li||pristine LPSC HT||Li symmetric cell demonstrates a decreased polarization and a much-enhanced cycle stability comparing to the Li||pristine LPSC||Li symmetric cell. [Display omitted] [ABSTRACT FROM AUTHOR]

The nanopatterning of gold nanoparticle (AuNP) arrays on an indium tin oxide (ITO) electrode using efficient and low-cost methods is described. This process used nanosphere lithography (NSL) encompassing the deposition of monolayered Polystyrene (PS) followed by a convective self-assembly drop coating protocol onto the ITO substrate that further acted as the mask after the AuNP assembly. The results showed that spin-coating allowed AuNPs to follow the contour and adhere to the PS nanospheres. The final products, after etching the PS, generated a highly ordered Au-nanohole array on an ITO substrate. The Au-nanohole arrays on the ITO electrode provided a greater surface area and successfully enhanced the peak current of electrochemical measurements by 82% compared with bare ITO and was used to detect Staphylococcus aureus 16S rRNA hybridization. In contrast to non-templated AuNP structures, the Au-nanohole arrays on the ITO electrode contributed to an optimum sensitivity improvement in DNA hybridization detection by 23%, along with an impressive limit of detection (LOD) of 10 pM. The high specificity of this distinguished structure was also achieved in the hybridization measurements of multi-analyte pathogens. These findings indicate that the combination of PS nanosphere lithography, followed by the spin-coating of AuNPs, leads to an inexpensive and simple engineering process that effectively generates uniform Au-nanohole arrays on ITO, which provides a greater surface area to optimize the electrochemical performance of the DNA biosensor. [ABSTRACT FROM AUTHOR]

An investigation of the cycling stability of anode-free batteries (AFBs) using dilute dual-salt electrolytes is conducted in a mixture of ether and carbonate solvents. Using the AFB configuration, various compositions of the dual-salt electrolyte were optimized and it was found that 0.9M-LiTFSI+0.3M-LiDFOB in FEC/TTE (2:3, v/v) is the best. An in-depth investigation of the electrochemical performance of AFB was conducted in this optimized dual-salt composition in comparison to 1.2 M LiTFSI in the same solvent ratio. Accordingly, the performance of Cu||NMC cell in the dual-salt electrolyte surpassed that of the single-salt. The relative better performance of the AFB in the dual-salt electrolyte is attributed to the co-existence of dual-ion (TFSI−&DFOB−) in the electrolyte, which enhanced conductivity and introduces entirely new interphases via preferential decomposition mechanisms. The newly formed interface is stable, ionically conductive, and able to intercept parasitic side reactions between the electrolyte solvent and the deposited Li by blocking electron and solvent flow towards the deposit. As a result of the unique interfacial chemistry brought by this dual-salt system, this electrolyte supports a unique CE (98.6%) and capacity retention (63%) in 4.5V Cu||NMC cell and exhibited >27% improvement over the single salt electrolyte after 50 cycles. [Display omitted] • Dilute dual-salt electrolyte delivers good performance. • Fluorinated salt and solvents result in a compact and stable LiF-rich SEI. • The synergy intercepted electrolyte consumption and gives better Li deposition morphology. • The combined effect gives the cell higher Coulombic efficiency and capacity retention. [ABSTRACT FROM AUTHOR]

Catalysts assumed that properly designed bimetallic systems would provide superior catalytic performance due to the cooperative effects between two atoms. Dual single‐atom catalyst (DSAC) PdN4/CuN4 is synthesized using a simple, cost‐effective, and efficient electrochemical reduction method. The palladium single‐atom is prepared first by electrochemical reduction of copper phthalocyanine to create defective N4 sites. The new structural feature is characterized by copper reduction from Cu‐N4 coordination and the formation of defected N4 (▫M‐N4) sites, which react with a Pd precursor and form PdN4 on the host surface. The DSAC PdN4/CuN4 technique synergistically improves electrocatalytic performance toward the ethylene glycol oxidation reaction. It possesses excellent glycolate selectivity (above 88%) in an alkaline solution with an onset oxidation potential as low as 0.6 V versus a reversible hydrogen electrode, compared to commercial Pd/C. The DSAC electrocatalyst is characterized by its high current density of 83.92 mA cm−2 and high faradic efficiency value (>80%) for glycolate at 1.0 VRHE. The findings suggest a promising method to synthesize the DSACs in varying transition metals to achieve highly efficient, selective, and environmentally friendly catalysts for different applications. [ABSTRACT FROM AUTHOR]

The multifunctional device combining electrochromic and photovoltaic performance is defined as a photoelectrochromic device (PECD), which is designed for self-powered smart window applications. Conventionally, Pt is used as an electrocatalyst to reduce the I 3 − in the electrolyte of PECD. However, the optical contrast of PECD with Pt-based counter electrode (CE) is restricted by an intrinsic opaque. In view of this problem, a polyaniline/reduced graphene oxide (PANI/rGO) nanocomposite electrocatalytic layer with highly optical transmittance and good electrocatalytic performance is designed to replace conventional Pt-based CE for further improving the optical performance of the corresponding PECD. Based on the advantages of low cost and promising electrocatalytic activity of PANI, highly transparent and remarkable conductive rGO is introduced to further boost up its electrical conductivity and electrochemical performance. To embed the rGO into the matrix of PANI uniformly, PANI/rGO nanocomposite is deposited on the conductive glass of ITO via electropolymerization. After systematically optimizing the film thickness and composition of PANI/rGO nanocomposite, the PECD with optimized PANI/rGO based CE possesses better optical contrast (ΔT = 26.8%) than that with Pt-based CE (ΔT = 9.4%), which clearly reveals that PANI/rGO nanocomposites with high optical transparency and electrocatalytic ability have the great potential to replace traditional Pt CE in PECDs. [Display omitted] • High optical transmittance and good electrocatalytic of PANI/rGO electrode is designed for PECD. • Conductive rGO is introduced to boost the electrochemical ability of PANI. • Quinoid rings of PANI in the nanocomposite became stable by π–π interactions with rGO. • PECD with CE of PANI/rGO possesses better optical contrast than that with CE of Pt. [ABSTRACT FROM AUTHOR]

DRIFTS (diffuse reflectance infrared Fourier-transformed spectroscopy) is applied to study the surface reactions over Li foil and Cu foil anodes when using the electrolyte of LiTFSI (LiN(SO 2 CF 3) 2) salt in DME (1,2-dimethoxyethane) and DOL (1,3-dioxolane) solvents, with/without LiNO 3 (LN) additive. The DRIFTS spectra at open circuit potential (OCV) indicate that DME and DOL are stable, while LiTFSI is chemically decomposed over Li but stable over Cu anode. The absorbance bands suggest that LiSO 2 CF 3 and Li 2 NSO 2 CF 3 species formed from LiTFSI decomposition over Li. LN is chemically decomposed over both Li and Cu anodes into LiNO 2 with Li 2 O as the likely accompanying species at OCV. During LSV (linear scan voltammetry) these surface species and also DOL and DME can be electrochemically reduced forming ROLi (CH 3 CH 2 OCH 2 Li/CH 3 OCH 2 CH 2 OLi and CH 3 OLi, respectively, from DOL and DME), Li 3 N (from TFSI− and LiNO 3), LiF and Li 2 SO 2 (from TFSI−), and Li 2 O (from LiNO 3). [Display omitted] [ABSTRACT FROM AUTHOR]

Electrochemical reduction of carbon dioxide (CO2RR) into value‐added chemicals is a promising tactic to mitigate global warming. However, this process resists catalyst preparation, low faradaic efficiency (FE%) towards multi‐carbon products, and insights into mechanistic understanding. Indeed, it is demonstrated that this Fe single‐atom catalyst (Fe SAC) exists in three oxygen coordination of Fe–(O)3 configuration in Nafion coated functionalized multi‐wall carbon nanotubes (Fe‐n‐f‐CNTs), which is obtained via a simple ionic exchange method under ambient conditions. The electrochemical performance reveals that Fe SACs achieve an FE of 45% and a yield rate of 56.42 µmol cm−2 h−1 at −0.8 VRHE for ethanol. In situ X‐ray analysis reveals that the Fe SACs have variable electronic states and keeps close +3 of the oxidation state at the potential range of CO2RR. The catalytic feature reduces the reaction energy and induces the electrons transferred to the adsorbed products intermediates of *COOH and *OCHO, thus promoting CO. The carboxylic functional group on the CNTs stabilizes the Fe active sites via electrostatic interaction, verified by density functional theory calculations. The yield rate of Fe SACs indicates that the Fe single‐atom site can instantly provide a large CO to help conversion of CO2‐to‐C2 product on the CNTs. [ABSTRACT FROM AUTHOR]

The electrochemical CO 2 -to-ethanol conversion bargains a promising approach to lowering CO 2 emission while yielding valuable chemical products. Here, we report the NiCu-SACs/N-C catalysts with cooperative dual heteroactive sites that achieve by far the highest catalytic activity for yielding ethanol with the unprecedented Faradaic efficiency of 92.2 % at the potential of −0.6 V versus RHE. The catalyst exhibits the lowest onset potential of −0.4 V versus RHE to catalyze CO 2 -to-ethanol conversion. In-operando X-ray absorption spectroscopy provides an interesting observation of restructuring behavior of dynamically generated Cu clusters from atomically distributed Cu single-atoms and reversible structural changes or oxidation states of Cu sites while Ni sites remain unchanged during the catalytic reactions. Our experimental analysis and DFT computation suggest that CO produced on Cu-N 4 /Ni-N 3 cooperative single atom sites undergoes C-C coupling, which is further reduced into ethanol. This strategy provides a new route to design selective and efficient catalysts for CO 2 -to-ethanol conversion. [Display omitted] • The cooperative dual heteroactive sites achieve by far the highest catalytic activity for yielding ethanol. • Operando XAS provides a restructuring behavior of dynamically generated Cu clusters from Cu single-atoms. • Our experimental analysis and DFT computation suggest that CO produced at the Ni sites undergoes C-C coupling on Cu sites. [ABSTRACT FROM AUTHOR]

Next-generation lithium-ion batteries will rely on nickel-rich layered oxides as cathode materials, but these materials are associated with structural and voltage losses. Magnesium (Mg) doping helps improve the performance of the nickel-rich layered cathode material. The Mg-modified LiNi 0·90 Mn 0·05 Co 0·05 O 2 (NMC-90) has been successfully synthesized through a co-precipitation technique followed by calcination at 850 °C. Modified NMC-90 exhibits better-organized layers and improved interfacial properties than pristine ones based on structural, chemical, and morphological studies. In a voltage range of 2.8–4.5 V, Mg (0.01 mol%)-doped NMC-90 (NMC-M1) composite cathode shows an excellent discharge capacity of 211.11 mAh/g, whereas pristine NMC-90 (NMC-M0) attains only 210.59 mAh/g at 0.1C with an initial coulombic efficiency of 89.5 % for NMC-M1 and 87.5 % for NMC-M0 cathode. The NMC-M1 cathode demonstrated an impressive enhancement in cyclability after 60 cycles compared to the NMC-M0 at 1C rate, in which the NMC-M1 cathode attains a high capacity retention of 80 % while the NMC-M0 cathode shows only 37 %. This study illustrates the importance of studying the effects of elemental doping on cell performance. It will drive the future development of cathode materials with high Ni and low Co content. [Display omitted] • Enhanced electrochemical performance of Mg-doped NMC-90 is discussed. • Magnesium doping helps to improve structural stability. • At 0.1C, NMC-M1 attains a specific capacity of 210.59 mAh/g with 89.5 % efficiency. • NMC-M1 retains 80 % of its capacity after 60 cycles at a 1C rate. • Promoting the Mg-doped NMC-90 cathode for practical applications. [ABSTRACT FROM AUTHOR]

Grand designs: A strategy for the design of Pt‐based bimetallic alloy catalysts for the oxidation of H2O2, which was achieved through a combination of DFT calculations and experiments, is reported. [ABSTRACT FROM AUTHOR]

In this work, the synthesis of a series of solid polymer electrolyte (SPE) derivatives of poly(ethylene glycol) methyl ether methacrylate (PEGMEMA), homogenously dispersed with TiO ceramic nano-filler, has been reported. The interactions between filler size and the length of the ethylene oxide (EO) polymer backbone are discussed, and transport properties such as ionic conductivity and cation transference number are determined. Results show that the improved performance of the SPE is due to an interaction between the ceramic filler and the entwining behavior of the PEGMEMA backbone. An optimal ceramic filler size and an appropriate length of EO have been suggested for the enhanced performance of SPE derivatives of PEGMEMA for a next-generation polymer battery. [ABSTRACT FROM AUTHOR]

Abstract: Highly conductive and hydration retentive mesoporous silica/Nafion and organically modified mesoporous silica/Nafion membranes are prepared by a surfactant templated sol–gel process involving Nafion solution and silica precursors. Spectroscopic analyses reveal that the in situ generation of a well-condensed silica network and organic (–PO3H2) functionalization of the inorganic segment are effectively achieved in the prepared membranes. The homogeneous dispersion of silica nanoparticles in the polymer matrix is apparent in electron micrographs. Structural analyses using small-angle X-ray scattering confirms the periodic short range structural order associated with these mesostructured hybrid membranes. These hybrid membranes exhibit an increased water uptake and an associated conductivity enhancement at 100% RH, compared to unmodified Nafion. More significantly, the functionalized silica/Nafion membranes show high proton conductivities at 80°C and 50% RH, which is more than 6 times higher than that of Nafion. Thermogravimetric analysis, low temperature DSC studies and a comparison of activation energies (E a) obtained from temperature-dependent conductivity plots of the membranes at different humidities, provide evidence for the better retention of water in the hybrid membranes compared to Nafion; thereby demonstrating the promising potential of these membranes to tolerate the variations in humidity at elevated temperatures. [Copyright &y& Elsevier]

Abstract: This study synthesizes poly(vinyl alcohol) (PVA)-based polymer electrolyte membranes by a two-step crosslinking process involving esterization and acetal ring formation reactions. This work also uses sulfosuccinic acid (SSA) as the first crosslinking agent to form an inter-crosslinked structure and a promoting sulfonating agent. Glutaraldehyde (GA) as the second crosslinking agent, reacts with the spare OH group of PVA and forms, not only a dense structure at the outer membrane surface, but also a hydrophobic protective layer. Compared with membranes prepared by a traditional one-step crosslinking process, membranes prepared by the two-step crosslinking process exhibit excellent dissolution resistance in water. The membranes become water-insoluble even at a molar ratio of SO3H/PVA–OH as high as 0.45. Moreover, the synthesized membranes also exhibit high proton conductivities and high methanol permeability resistance. The current study measures highest proton conductivity of 5.3×10−2 Scm−1 at room temperature from one of the synthesized membranes, higher than that of the Nafion® membrane. Methanol permeability of the synthesized membranes measures about 1×10−7 cm2 S−1, about one order of magnitude lower than that of the Nafion® membrane. [Copyright &y& Elsevier]

Zinc metal is considered a promising anode material for aqueous zinc ion batteries. However, it suffers from dendrite growth, corrosion, and low coulombic efficiency (CE) during plating/stripping. Herein, a concentrated hybrid (4 m Zn(CF3SO3)2 + 2 m LiClO4) aqueous electrolyte (CHAE) to overcome the challenges facing the Zn anode is reported. The developed electrolyte achieves dendrite‐free Zn plating/stripping and obtains an excellent CE of ≈100%, surpassing the previously reported values. The combination of synchrotron‐based in operando transmission X‐ray microscopy, X‐ray diffraction, and ex situ X‐ray photoelectron spectroscopy analyses indicate that the denser, anion‐derived passivation layer formed using the CHAE facilitates homogeneous current distribution and better prevents freshly deposited Zn from directly contacting the electrolyte than the looser, solvent‐derived layers formed from a dilute hybrid aqueous electrolyte (DHAE). The beneficial effects of the CHAE on the compact, dense, and stable salt‐anion‐derived passivation layer can be attributed to its unique solvation structure, which suppresses the water‐related side reactions and widens the electrochemical potential window. In the hybrid Zn||LiFePO4 configuration, the CHAE‐based cell delivered a stable performance of CE >99% and capacity retention >90% after 285 cycles. In contrast, the DHAE‐based cell exhibits capacity retention of <65% after 170 cycles. [ABSTRACT FROM AUTHOR]

Abstract: Layered LiAl1/3−x Co x Ni1/3Mn1/3O2 (0≦ x ≦1/3) compounds were studied via the combination of computational and experimental approach. The calculated voltage curve of LiNi1/3Al1/3Mn1/3O2 compound is presented, indicating it is of great potential for a cathode material of lithium-ion batteries. Unfortunately, it was found that the LiNi1/3Al1/3Mn1/3O2 compound without impurity phase could not be synthesized via a sol–gel process. To obtain a layered compound without impurity phase, partial of Al is replaced by Co in LiNi1/3Al1/3Mn1/3O2 compound in this study. Layered LiAl1/3−x Co x Ni1/3Mn1/3O2 (0≦ x ≦1/3) compounds were synthesized via sol–gel reaction at 900°C under a oxygen stream. Single phase of the LiAl1/3−x Co x Ni1/3Mn1/3O2 in 1/6≦ x ≦1/3 region could be prepared successfully. The discharge capacity and conductivity increased with an increase in the Co-substitution content. The enhancement of the conductivity and phase purity by the introduction of Co content shows profound influence on the performance of the LiAl1/3−x Co x Ni1/3Mn1/3O2 compounds. [Copyright &y& Elsevier]

Abstract: Synthesis and characterization of LiNi x Co1−2x Mn x O2 (1/3≤ x ≤1/2) electrode powders prepared by a sol–gel method were investigated. The synthesized LiNi x Co1−2x Mn x O2 materials with single phase and R m layered structure were confirmed from X-ray diffraction analysis. The particle size distribution of the materials synthesized by the sol–gel process is quite uniform. Increasing the x value in the synthesized LiNi x Co1−2x Mn x O2 powder leads to decrease its particle size and increase its cation mixing. The average particle size for the LiNi0.375Co0.25Mn0.375O2 powder was found to be an order of 0.3–0.4μm. The best specific capacity of 192mAhg−1 was obtained for the LiNi0.375Co0.25Mn0.375O2 electrode with good capacity retention among the synthesized materials cycled at 0.1C in the potential between 3.0 and 4.5V at room temperature. Although structural parameters of the LiNi0.375Co0.25Mn0.375O2 powder are similar to those of the LiNi1/3Co1/3Mn1/3O2 powder, its specific capacity is higher due to the increase of the stoichiometry of active site Ni. The increase of Ni and Mn content could reduce cost of the materials. It was found that the cell performance of the LiNi x Co1−2x Mn x O2 electrode drops dramatically and its cation mixing increases while the x value is higher than 0.4. [Copyright &y& Elsevier]

Abstract: The application of micro-systems, designed to contain monitoring or actuating devices is often hampered by energy supply. For systems with low power demands, the use of implanted battery and inductive links for wireless energy transfer to the remote system is widely acknowledged solution. But these energy supply system are limited by the energy shortage and inductive coils alignment. The misalignment of wireless energy transfer loops causes the low energy transfer efficiency and inexact induced potential. Although the implanted battery can offer more stable energy supply, the shortage in energy storage limited its application and durability. In this work, we developed the wireless microwave charging module to overcome the disadvantages of previous methods. The wireless microwave charging module can charge the implanted lithium ion battery in a suitable distance by tuning the power input and the implanted lithium ion battery shows excellent cycleability after 20 cycles of wireless charging. Although the conversion of the wireless microwave charging is only 2–5%, it can be improved by using other designs of antenna (microwave generation part) and rectify antenna (receive and conversion part). The cell performance of the spinel compound for the wireless energy transfer is better than that of the layered compound. [Copyright &y& Elsevier]

Abstract: Aluminum-doped lithium iron phosphate was synthesized with a modified sol–gel process. The sol–gel derived cathodes show much higher conductivity than those prepared by a solid-state method. The conductivity is 8×10−2 Scm−1 for the Al-doped LiFePO4/carbon composite powders synthesized at 850°C for 2h, as determined using AC impedance spectroscopy. The electrodes consisting of the Al-doped LiFePO4/carbon composite powders were fabricated for the electrochemical characterization and showed a specific capacity of about 150mAhg−1 at C/40 rate. Not only the conductivity of the crystal lattice but also the conductivity of the grain boundary is enhanced for the nano-sized Al-doped LiFePO4/carbon composite powders. [Copyright &y& Elsevier]

The effect of surfactants on the transient phenomena of the codeposition of PTFE with electroless Ni–P coating at the early stage was investigated in this study. Two surfactants (CTAB and FC134) are utilized for comparison. The composition variation of the deposited layer is strongly related to the cathodic reactivity of the surfactants depending on the substrates at the early stage. When the cathodic reactivity of the surfactants is higher, correspondingly the PTFE particles are more easily embedded in the codeposition layer. The volume fraction of PTFE loading increases with the growth of the codeposition layer when the cathodic reactivity of surfactants on a substrate is less than that on the deposited layer. On the contrary, the volume fraction of PTFE loading decreases with the growth of the codeposition layer. Increasing the PTFE loading with the growth of the codeposition layer would provide good adhesion between the substrate and the codeposition layer. [Copyright &y& Elsevier]

[Display omitted] • The Cu-Sn@SFPH features Sn as the bottom layer and SrF 2 /PVDF-HFP as the top layer. • SrF 2 and PVDF-HFP act as a high-surface-area framework for accommodating Li-ions. • The LiF-rich SEI promotes Li+ transfer, and Li-Sn/Li-Sr alloys serve as nucleation. • The Cu-Sn@SFPH electrode anode-free pouch cell demonstrates outstanding performance. • This strategy demonstrates the potential for making AFLMBs a practical battery. Anode-free lithium metal batteries (AFLMBs) have sparked considerable attention in recent years because of their potential for high energy density; however, they suffer from severe Li dendrite growth and unstable solid electrolyte interphase (SEI), which typically result in rapid capacity decay. Herein, we demonstrate a long-life anode-free pouch cell by designing a dual-coating protective layer (Cu-Sn@SFPH) electrode with Sn-coated Cu (denoted as Cu-Sn) as the bottom layer and SrF 2 nanoparticles strengthened by poly (vinylidene fluoride)-co-hexafluoropropylene (PVDF-HFP) as the top layer. The in-situ formed LiF-rich SEI enables fast Li+ transfer, while the lithiophilic Li-Sn and Li-Sr alloy layers serve as nucleation seeds for uniform Li deposition. The dual-coated Cu electrode in the Cu-Sn@SFPH||Li cell exhibits remarkable cycling stability for more than 3,200 h at a capacity of 2 mAh cm−2. The NCM111||Cu-Sn@SFPH pouch cell demonstrates outstanding performance with a capacity retention of 72.1 % and an average Coulombic efficiency (CE) of 99.9 % for 120 cycles. Under practical conditions, with NCM cathodes and a lean electrolyte volume, this design strategy opens a new approach to AFLMBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • H-bond interactions in Composite-HT-GPE enhance interface stability and limit dendritic Li. • Cu-adherent GPE initiates atomic alignment and generates LiF-flourished SEI. • Anion trapping ability of F-PI promotes facile Li+-transport, with a high t+ of 0.7. • Improved Li-ion kinetics and uniform plating/stripping in an AFLMB. • Cu||NMC811 displayed a capacity retention of ∼ 70 % after 100 cycles. Lithium-metal battery advancement has been restricted due to increasing apprehensions about leakage-related safety issues and the unavoidable formation of dendrites connected with liquid electrolytes. Gel polymer electrolytes (GPEs) have the benefits of both solid polymer and liquid electrolytes and thus appear to be a more viable alternative in energy storage devices. Poly(vinylidene fluoride-co-hexafluoropropylene (PVDF-HFP)-based GPE is known for its high dielectric constant and wide potential window. Fluorinated polyimide (F-PI) has outstanding thermal and oxidative stability. Herein, we prepare a composite GPE exhibiting a porous 3D cross-linked structure by combining these two polymers via thermal treatment, enabling H-bonding interaction between F-PI (N-H) and (-F) PVDF-HFP. Further, upon gelation, the amide bond (N-H moiety) in F-PI possesses unique anion-trapping (FSI-) by strong H-bonding interaction. This interaction restricts anion's dynamics, making them immobile and facilitating Li-ion transport. It improves the Li-ion kinetics and uniformity during the plating/stripping in an anode-free lithium metal battery (AFLMB) (Cu||NMC811). With a high Li+ transference number of 0.7, this GPE displays exceptional cycling stability with a retention of ∼ 70 % after 100 cycles. [ABSTRACT FROM AUTHOR]