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Abstract The sluggish kinetics of sulfur conversions have long been hindering the implementation of fast and efficient sulfur electrochemistry in lithium–sulfur (Li–S) batteries. In this regard, herein the unique chromium boride (CrB) is developed via a well‐confined mild‐temperature thermal reaction to serve as an advanced sulfur electrocatalyst. Its interstitial‐alloy nature features excellent conductivity, while the nano‐lamination architecture affords abundant active sites for host‐guest interactions. More importantly, the CrB nanocatalyst demonstrates a dual sulphophilicity with simultaneous Cr─S and B─S bondage for establishing strong interactions with the intermediate polysulfides. As a result, significant stabilization and promotion of sulfur redox behavior can be achieved, enabling an excellent Li–S cell cyclability with a minimum capacity fading rate of 0.0176% per cycle over 2000 cycles and a favorable rate capability up to 7 C. Additionally, a high areal capacity of 5.2 mAh cm−2, and decent cycling and rate performances are still attainable under high sulfur loading and low electrolyte dosage. This work offers a facile approach and instructive insights into metal boride sulfur electrocatalyst, holding a good promise for pursuing high‐efficiency sulfur electrochemistry and high‐performance Li–S batteries.

Lithium-sulfur batteries (LSBs) are promising candidates for next-generation high-efficiency energy storage, yet their practical implementation is seriously impeded by the parasitic shuttle effect and sluggish reaction kinetics. Herein, we develop a unique Cu, Co layered double hydroxide (CuCo-LDH) with a hollow and hierarchical structure as an advanced electrocatalyst to tackle these challenges. Combining the compositional, architectural, and chemical advantages, the as-developed CuCo-LDH enables facile charge transfer, fully exposed active interfaces, and strong interactions with polysulfides via metal–sulfur bonding. When employed in the functional separator, a reliable polysulfide barrier can be established against the shuttling behavior, while the excellent catalytic activity realizes fast and efficient sulfur electrochemistry. As a result, the CuCo-LDH-based LSBs achieve a well-restrained capacity decay of 0.049% per cycle over 500 cycles together with a good rate capability up to 5 C. Moreover, a favorable areal capacity of 4.39 mAh cm−2 and decent cyclability are still attainable even under a high sulfur loading of 4.2 mg cm−2 and a low E/S ratio of 6 ml g−1. This work affords a feasible and instructive pathway toward advanced sulfur electrocatalysts as well as high-performance LSBs.

Stable solid electrolyte interface (SEI) is heavily investigated due to its role in improving lithium metal batteries. Here, the authors present a new strategy by employing electrolyte additives to construct stable multifunctional SEI via in situ anionic polymerization.

Abstract Rational construction of sulfur electrodes is essential in pursuit of practically viable lithium–sulfur (Li–S) batteries. Herein, bimetallic NiCo‐layered double hydroxide (NiCo‐LDH) with a unique hierarchical micro‐nano architecture is developed as an advanced sulfur reservoir for Li–S batteries. Compared with the monometallic Co‐layered double hydroxide (Co‐LDH) counterpart, the bimetallic configuration realizes much enriched, miniaturized, and vertically aligned LDH nanosheets assembled in hollow polyhedral nanoarchitecture, which geometrically benefits the interface exposure for host–guest interactions. Beyond that, the introduction of secondary metal intensifies the chemical interactions between layered double hydroxide (LDH) and sulfur species, which implements strong sulfur immobilization and catalyzation for rapid and durable sulfur electrochemistry. Furthermore, the favorable NiCo‐LDH is architecturally upgraded into closely packed micro‐nano clusters with facilitated long‐range electron/ion conduction and robust structural integrity. Due to these attributes, the corresponding Li–S cells realize excellent cyclability over 800 cycles with a minimum capacity fading of 0.04% per cycle and good rate capability up to 2 C. Moreover, highly reversible areal capacity of 4.3 mAh cm−2 can be achieved under a raised sulfur loading of 5.5 mg cm−2. This work provides not only an effective architectural design but also a deepened understanding on bimetallic LDH sulfur reservoir for high‐performance Li–S batteries.

Lithium sulfur batteries show capacity and cost advantages, but suffer from the insulating sulfur, shuttling effect and volume fluctuation. To address these challenges, the authors synthesize foldable composite electrodes with carbon nanotubes interpenetrating metal-organic frameworks.

Composite-polymer-electrolytes (CPEs) embedded with advanced filler materials offer great promise for fast and preferential Li+ conduction. The filler surface chemistry determines the interaction with electrolyte molecules and thus critically regulates the Li+ behaviors at the interfaces. Herein, we probe into the role of electrolyte/filler interfaces (EFI) in CPEs and promote Li+ conduction by introducing an unsaturated coordination Prussian blue analog (UCPBA) filler. Combining scanning transmission X-ray microscope stack imaging studies and first-principle calculations, fast Li+ conduction is revealed only achievable at a chemically stable EFI, which can be established by the unsaturated Co-O coordination in UCPBA to circumvent the side reactions. Moreover, the as-exposed Lewis-acid metal centers in UCPBA efficiently attract the Lewis-base anions of Li salts, which facilitates the Li+ disassociation and enhances its transference number (tLi +). Attributed to these superiorities, the obtained CPEs realize high room-temperature ionic conductivity up to 0.36 mS cm-1 and tLi + of 0.6, enabling an excellent cyclability of lithium metal electrodes over 4,000 h as well as remarkable capacity retention of 97.6% over 180 cycles at 0.5 C for solid-state lithium-sulfur batteries. This work highlights the crucial role of EFI chemistry in developing highly conductive CPEs and high-performance solid-state batteries. [ABSTRACT FROM AUTHOR]

Graphene has become one of the most readily used materials in wearable sensing technology due to its unique properties of lightweight, ultrahigh carrier mobility, good environmental stability and robust mechanical flexibility. However, efforts based on graphene have still rarely been made for fabricating device-level wearable sensors. In addition, few review articles related to these aspects have been reported. In this work, recent research progress of wearable graphene sensors for healthcare, motion detections, and environment monitoring, is briefly reviewed. Also, the challenges and perspectives for the future generation of wearable graphene sensors are also highlighted. This work provides a comprehensive understanding on the present research situations and challenges for wearable graphene devices for sensing. [ABSTRACT FROM AUTHOR]

Organic-inorganic solid-state composite electrolyte is of great promise to support the high-performance and safe energy storage applications. Herein we developed an ionic liquid-assisted PEO-LAGP-EMITFSI composite electrolyte (PLE) for advanced solidstate lithium ion batteries (LIBs). The EMITFSI ionic liquid was employed as the plasticizer to effectively lower the crystallinity of the composite and thus significantly enhance the ionic conductivity up to 8.85 × 10-4 S cm-1 at 60°C. Combined with its good electrochemical stability and decent ion transference selectiveness, the optimized PLE electrolyte contributed to an excellent battery performance in LiFePO4/PLE/Li configuration with high capacity retention of 114.7 mAh g-1 after 120 cycles and good rate capability of 112.2 mAh g-1 at 1C, indicating its great potential in developing high-performance solid-state LIBs. [ABSTRACT FROM AUTHOR]

In this work, unique porous carbon sheets (PCSs) are developed via a facile synthesis. The obtained PCS delivers long-range conductive framework, abundant active interfaces, rich element doping, and notably a high inner porosity that builds up an admirable 3D network for multidirectional ion transfer. Such unique architecture and surface chemistry enable ultrafast sulfur electrochemistry as well as high-efficiency inhibition on polysulfide shuttling via the dually physical and chemical sulfur confinement. The PCS-based sulfur electrodes achieve superb rate capability up to 10 C, outstanding cyclability over 1000 cycles, and high areal capacity of 4.8 mA h cm-2. This work offers an appealing model of material engineering for fast and reliable lithium-sulfur batteries, as well as guidance for rational structural design in extended energy storage and conversion systems. [ABSTRACT FROM AUTHOR]

Three new secondary metabolites pestalothenins A–C (1–3), including two new humulane-derived sesquiterpeniods (1 and 2) and one new caryophyllene-derived sesquiterpeniod (3), together with five known compounds (4–8) were isolated from the crude extract of the plant endophytic fungus Pestalotiopsis theae (N635). Their structures were elucidated by the extensive analyses of HRESIMS and NMR spectroscopic data. The absolute configurations of 1–3 were determined by comparison of experimental and calculated electronic circular dichroism (ECD) spectra. The cytotoxic effects of these compounds were evaluated in vitro. Compound 6 showed moderate cytotoxicity against T24 and MCF7 cell lines. In addition, compounds 1–8 were also evaluated for antibacterial activity.

Three new andrastin-type meroterpenoids penimeroterpenoids A–C (1–3) together with two known analogs (4 and 5) were isolated from the cultures of the marine-derived Penicillium species (sp.). The structures of the new compounds were elucidated on the basis of 1- and 2-dimensional (1D/2D) Nuclear Magnetic Resonance (NMR) spectroscopic and mass spectrometric analysis. The absolute configurations of 1–3 were determined by comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Compound 1 showed moderate cytotoxicity against A549, HCT116, and SW480 cell lines.