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The reaction rate bottleneck during interconversion between insulating S8 (S) and Li2S fundamentally leads to incomplete conversion and restricted lifespan of Li−S battery, especially under high S loading and lean electrolyte conditions. Herein, we demonstrate a new catalytic chemistry: soluble semiquinone, 2‐tertbutyl‐semianthraquinone lithium (Li+TBAQ⋅−), as both e‐/Li+ donor and acceptor for simultaneous S reduction and Li2S oxidation. The efficient activation of S and Li2S by Li+TBAQ⋅− in the initial discharging/charging state maximizes the amount of soluble lithium polysulfide, thereby substantially improve the rate of solid–liquid‐solid reaction by promoting long‐range electron transfer. With in situ Raman spectra and theoretical calculations, we reveal that the activation of S/Li2S is the rate‐limiting step for effective S utilization under high S loading and low E/S ratio. Beyond that, the S activation ratio is firstly proposed as an accurate indicator to quantitatively evaluate the reaction rate. As a result, the Li−S batteries with Li+TBAQ⋅− deliver superior cycling performance and over 5 times higher S utilization ratio at high S loading of 7.0 mg cm−2 and a current rate of 1 C compared to those without Li+TBAQ⋅−. We hope this study contributes to the fundamental understanding of S redox chemical and inspires the design of efficient catalysis for advanced Li−S batteries. [ABSTRACT FROM AUTHOR]

Organic electrode materials (OEMs), valued for their sustainability and structural tunability, have been attracting increasing attention for wide application in sodium‐ion batteries (SIBs) and other rechargeable batteries. However, most OEMs are plagued with insufficient specific capacity or poor cycling stability. Therefore, it′s imperative to enhance their specific capacity and cycling stability through molecular design. Herein, we designed and synthesized a heteroaromatic molecule 2,3,8,9,14,15‐hexanol hexaazatrinaphthalene (HATN‐6OH) by the synergetic coupling of catechol (the precursor of ortho‐quinone)/ortho‐quinone functional groups and HATN conjugated core structures. The abundance of catechol/ortho‐quinone and imine redox‐active moieties delivers a high specific capacity of nine‐electron transfer for SIBs. Most notably, the π–π interactions and intermolecular hydrogen bond forces among HATN‐6OH molecules secure the stable long‐term cycling performance of SIBs. Consequently, the as‐prepared HATN‐6OH electrode exhibited a high specific capacity (554 mAh g−1 at 0.1 A g−1), excellent rate capability (202 mAh g−1 at 10 A g−1), and stable long‐term cycling performance (73 % after 3000 cycles at 10 A g−1) in SIBs. Additionally, the nine‐electron transfer mechanism is confirmed by systematic density functional theory (DFT) calculation, attenuated total reflection Fourier transform infrared spectroscopy (ATR‐FTIR), and Raman analysis. The achievement of the synergetic coupling of the redox‐active sites on OEMs could be an important key to the enhancement of SIBs and other metal‐ion batteries. [ABSTRACT FROM AUTHOR]

Not only high efficiency but also high selectivity of the electrocatalysts is crucial for high‐performance, low‐cost, and sustainable energy storage applications. Herein, we systematically investigate the edge effect of carbon‐supported single‐atom catalysts (SACs) on oxygen reduction reaction (ORR) pathways (two‐electron (2 e−) or four‐electron (4 e−)) and conclude that the 2 e−‐ORR proceeding over the edge‐hosted atomic Co−N4 sites is more favorable than the basal‐plane‐hosted ones. As such, we have successfully synthesized and tuned Co‐SACs with different edge‐to‐bulk ratios. The as‐prepared edge‐rich Co−N/HPC catalyst exhibits excellent 2 e−‐ORR performance with a remarkable selectivity of ≈95 % in a wide potential range. Furthermore, we also find that oxygen functional groups could saturate the graphitic carbon edges under the ORR operation and further promote electrocatalytic performance. These findings on the structure–property relationship in SACs offer a promising direction for large‐scale and low‐cost electrochemical H2O2 production via the 2 e−‐ORR. [ABSTRACT FROM AUTHOR]

Bioinspired asymmetric nanofluidic ion channels with ionic diode behavior that can boost the osmotic energy (so‐called blue energy) conversion are highly desirable, especially if they can be easily constructed and modified. Two‐dimensional (2D) metal carbides and nitrides, known as MXenes, combine hydrophilic surfaces and tunable surface charge properties, providing a shortcut to prepare asymmetric nanofluidic ion channels. Here, we report a mechanically robust, flexible, and scale‐up‐friendly asymmetric Ti3C2Tx MXene‐based ionic diode membrane with a highly rectified current and demonstrate its potential use in reverse electrodialysis osmotic energy conversion. Under the salinity gradient of synthetic seawater and river water, our ionic diode membrane‐based generator's power density is 8.6 W m−2 and up to 17.8 W m−2 at a 500‐fold salinity gradient, outperforming the state‐of‐the‐art membranes. The design of MXene‐based ionic diode‐type membrane provides a facile and general strategy in developing large‐scale 2D nanofluidics and selective ion transport. [ABSTRACT FROM AUTHOR]

Electronic structure engineering on electrode materials could bring in a new mechanism to achieve high energy and high power densities in sodium ion batteries. Herein, we design and create Co vacancies at the interface of atomically thin CoSe2/graphene heterostructure and obtain Co1−xSe2/graphene heterostructure electrode materials that facilitate significant Na+ intercalation pseudocapacitance. Density functional theory (DFT) calculation suggests that the Na+ adsorption energy is dramatically increased, and the Na+ diffusion barrier is remarkably reduced due to the introduction of Co vacancy. The optimized electrode delivers a superior capacity of 673.6 mAh g−1 at 0.1 C, excellent rate capability of 576.5 mAh g−1 at 2.0 C and ultra‐long life up to 2000 cycles. Kinetics analysis indicates that the enhanced Na+ storage is mainly attributed to the intercalation pseudocapacitance induced by Co vacancies. This work suggests that the creation of cation vacancy could bestow heterostructured electrode materials with pseudocapacitive Na+ intercalation for high‐capacity and high‐rate energy storage. [ABSTRACT FROM AUTHOR]

Dual‐ion batteries (DIBs) inherently suffer from limited energy density. Proposed here is a strategy to effectively tackle this issue by employing locally ordered graphitized carbon (LOGC) cathodes. Quantum mechanical modeling suggests that strong anion–anion repulsions and severe expansion at the deep‐charging stage raise the anion intercalation voltage, therefore only part of the theoretical anion storage sites in graphite is accessible. The LOGC interconnected with disordered carbon is predicted to weaken the interlaminar van der Waals interactions, while disordered carbons not only interconnect the dispersed nanographite but also partially buffer severe anion–anion repulsion and offer extra capacitive anion storage sites. As a proof‐of‐concept, ketjen black (KB) with LOGC was used as a model cathode for a potassium‐based DIB (KDIB). The KDIB delivers an unprecedentedly high specific capacity of 232 mAh g−1 at 50 mA g−1, a good rate capability of 110 mAh g−1 at 2000 mA g−1, and excellent cycling stability of 1000 cycles without obvious capacity fading. [ABSTRACT FROM AUTHOR]

The poor cycling stability resulting from the large volume expansion caused by lithiation is a critical issue for Si‐based anodes. Herein, we report for the first time of a new yolk–shell structured high tap density composite made of a carbon‐coated rigid SiO2 outer shell to confine multiple Si NPs (yolks) and carbon nanotubes (CNTs) with embedded Fe2O3 nanoparticles (NPs). The high tap density achieved and superior conductivity can be attributed to the efficiently utilised inner void containing multiple Si yolks, Fe2O3 NPs, and CNTs Li+ storage materials, and the bridged spaces between the inner Si yolks and outer shell through a conductive CNTs "highway". Half cells can achieve a high area capacity of 3.6 mAh cm−2 and 95 % reversible capacity retention after 450 cycles. The full cell constructed using a Li‐rich Li2V2O5 cathode can achieve a high reversible capacity of 260 mAh g−1 after 300 cycles. [ABSTRACT FROM AUTHOR]

Membranes. In their Research Article (e202206152), Jian Xue, Jürgen Caro, Haihui Wang et al. report a bioinspired Ti3C2Tx MXene‐based ionic diode membrane for osmotic energy conversion with extraordinary ionic rectification. [ABSTRACT FROM AUTHOR]

Keywords: Ionic Diode; MXene Membrane; Nanofluidic; Osmotic Energy EN Ionic Diode MXene Membrane Nanofluidic Osmotic Energy 1 1 1 10/04/22 20221010 NES 221010 B Membranes b . Frontispiece: Bioinspired Ti3C2Tx MXene-Based Ionic Diode Membrane for High-Efficient Osmotic Energy Conversion In their Research Article (e202206152), Jian Xue, Jürgen Caro, Haihui Wang et al. report a bioinspired Ti SB 3 sb C SB 2 sb T SB x sb MXene-based ionic diode membrane for osmotic energy conversion with extraordinary ionic rectification. [Extracted from the article]