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The electrification of the transport sector has created an increasing demand for lithium‐ion batteries that can provide high power intermittently while maintaining a high energy density. Given the difficulty in designing a single redox material with both high power and energy density, electrodes based on composites of several electroactive materials optimized for power or capacity are being studied extensively. Among others, fast‐charging LiFePO4 and high energy Li(NixMnyCoz)O2 are commonly employed in industrial cell manufacturing. This study focuses on comparing different approaches to combining these two active materials into a single electrode. These arrangements were compared using standard electrochemical (dis)charge procedures and using synchrotron X‐ray fluorescence to identify variations in solution concentration gradient formation. The electrochemical performance of the layered electrodes with the high‐power material on top is found to be enhanced relative to its blended electrode counterpart when (dis)charged at the same specific currents. These findings highlight dual‐layer lithium‐ion batteries as an inexpensive way of increasing energy and power density of lithium‐ion batteries as well as a model system to study and exploit the synergistic effects of blended electrodes. [ABSTRACT FROM AUTHOR]

Liubao tea (LBT) is a unique microbial‐fermented tea that boasts a long consumption history spanning 1500 years. Through a specific post‐fermentation process, LBT crafted from local tea cultivars in Liubao town Guangxi acquires four distinct traits, namely, vibrant redness, thickness, aging aroma, and purity. The intricate transformations that occur during post‐fermentation involve oxidation, degradation, methylation, glycosylation, and so forth, laying the substance foundation for the distinctive sensory traits. Additionally, LBT contains multitudinous bioactive compounds, such as ellagic acid, catechins, polysaccharides, and theabrownins, which contributes to the diverse modulation abilities on oxidative stress, metabolic syndromes, organic damage, and microbiota flora. However, research on LBT is currently scattered, and there is an urgent need for a systematical recapitulation of the manufacturing process, the dominant microorganisms during fermentation, the dynamic chemical alterations, the sensory traits, and the underlying health benefits. In this review, current research progresses on the peculiar tea varieties, the traditional and modern process technologies, the substance basis of sensory traits, and the latent bioactivities of LBT were comprehensively summarized. Furthermore, the present challenges and deficiencies that hinder the development of LBT, and the possible orientations and future perspectives were thoroughly discussed. By far, the productivity and quality of LBT remain restricted due to the reliance on labor and experience, as well as the incomplete understanding of the intricate interactions and underlying mechanisms involved in processing, organoleptic quality, and bioactivities. Consequently, further research is urgently warranted to address these gaps. [ABSTRACT FROM AUTHOR]

Developing metallic nanocatalysts with high reaction activity, selectivity and practical durability is a promising and active subfield in electrocatalysis. In the classical "bottom‐up" approach to synthesize stable nanomaterials by chemical reduction, stabilizing additives such as polymers or organic surfactants must be present to cap the nanoparticle to prevent material bulk aggregation. In recent years, biological systems have emerged as green alternatives to support the uncoated inorganic components. One key advantage of biological templates is their inherent ability to produce nanostructures with controllable composition, facet, size and morphology under ecologically friendly synthetic conditions, which are difficult to achieve with traditional inorganic synthesis. In addition, through genetic engineering or bioconjugation, bio‐templates can provide numerous possibilities for surface functionalization to incorporate specific binding sites for the target metals. Therefore, in bio‐templated systems, the electrocatalytic performance of the formed nanocatalyst can be tuned by precisely controlling the material surface chemistry. With controlled improvements in size, morphology, facet exposure, surface area and electron conductivity, bio‐inspired nanomaterials often exhibit enhanced catalytic activity towards electrode reactions. In this Review, recent research developments are presented in bio‐approaches for metallic nanomaterial synthesis and their applications in electrocatalysis for sustainable energy storage and conversion systems. [ABSTRACT FROM AUTHOR]

Keywords: electrode architecture; power density; fast charge; blended electrode; X-ray fluorescence EN electrode architecture power density fast charge blended electrode X-ray fluorescence 1 1 1 11/07/23 20231102 NES 231102 B The Front Cover b shows Li-metal cells which contain two active materials (red and blue). Front Cover: Exploring the Synergistic Effects of Dual-Layer Electrodes for High Power Li-Ion Batteries (ChemElectroChem 21/2023) Electrode architecture, power density, fast charge, blended electrode, X-ray fluorescence. [Extracted from the article]

Although the platelet structure of calcium hexaluminate (CaAl12O19, or CA6) grains can strengthen and toughen the Al2O3-MgO-CaO system materials designed in the high-alumina region, it also results in poor densification and subsequent accelerated slag penetration for refractory application. Considering this aspect, MgAl2O4-CaAl4O7-CaAl12O19 composite was fabricated by solid-state reaction sintering in this work, and the effect of ZrO2 addition on densification and mechanical properties was investigated. The results showed that the CA6 grains presented a more equiaxed morphology by addition of ZrO2, contributing to form highly dense microstructures after heating at 1600°C without evident grain coarsening. The compressive strength and flexural strength were greatly enhanced mainly due to the significant decrease in porosity and pore sizes. Besides, the increased content of ZrO2 plays an active role in toughening this composite attributed to the dense microstructure and strong bonding with higher strength, as well as considerable t-ZrO2 transformability. [ABSTRACT FROM AUTHOR]

Cover Feature: Recent Advances in Bio-Templated Metallic Nanomaterial Synthesis and Electrocatalytic Applications (ChemSusChem 3/2021) Keywords: biological templates; electrocatalysis; energy conversion/storage; nanomaterials; surface functionalization EN biological templates electrocatalysis energy conversion/storage nanomaterials surface functionalization 756 756 1 02/17/21 20210205 NES 210205 B The Cover Feature b (designed by Dr. Nicholas A. Payne, University of Western Ontario) shows the different components required for applying bio-templated metallic nanomaterials in electrocatalysis. Biological templates, electrocatalysis, energy conversion/storage, nanomaterials, surface functionalization. [Extracted from the article]