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Nickel‐rich (Ni≥90 %) layered cathodes are critical materials for achieving higher‐energy‐density and lower‐cost next‐generation Li‐ion batteries (LIBs). However, their bulk and interface structural instabilities significantly impair their electrochemical performance, thus hindering their widespread adoption in commercial LIBs. Exploiting Ti and Mo diffusion chemistry, we report one‐step calcination to synthesize bulk‐to‐surface modified LiNi0.9Co0.09Mo0.01O2 (NCMo90) featuring a 5 nm Li2TiO3 coating on the surface, a Mo‐rich Li+/Ni2+ superlattice at the sub‐surface, and Ti‐doping in the bulk. Such a multi‐functional structure effectively maintains its structural integrity upon cycling. As a result, such NCMo90 exhibits a high initial capacity of 221 mAh g−1 at 0.1 C, excellent rate performance (184 mAh g−1 at 5 C), and high capacity retention of 94.0 % after 500 cycles. This work opens a new avenue to developing industry‐applicable Ni‐rich cathodes for next‐generation LIBs. [ABSTRACT FROM AUTHOR]

A solid‐state electrolyte (SSE), which is a solid ionic conductor and electron‐insulating material, is known to play a crucial role in adapting a lithium metal anode to a high‐capacity cathode in a solid‐state battery. Among the various SSEs, the single Li‐ion conductor has advantages in terms of enhancing the ion conductivity, eliminating interfacial side reactions, and broadening the electrochemical window. Covalent organic frameworks (COFs) are optimal platforms for achieving single Li‐ion conduction behavior because of well‐ordered one‐dimensional channels and precise chemical modification features. Herein, we study in depth three types of Li‐carboxylate COFs (denoted LiOOC‐COFn, n = 1, 2, and 3) as single Li‐ion conducting SSEs. Benefiting from well‐ordered directional ion channels, the single Li‐ion conductor LiOOC‐COF3 shows an exceptional ion conductivity of 1.36 × 10−5 S cm−1 at room temperature and a high transference number of 0.91. Moreover, it shows excellent electrochemical performance with long‐term cycling, high‐capacity output, and no dendrites in the quasi‐solid‐state organic battery, with the organic small molecule cyclohexanehexone (C6O6) as the cathode and the Li metal as the anode, and enables effectively avoiding dissolution of the organic electrode by the liquid electrolyte. [ABSTRACT FROM AUTHOR]

The use of conductive polymer composites (CPCs) for strain sensing applications has attracted intense interest lately. The stability and sensitivity of resistivity -- strain behaviour are thought to be important issues, but systematic investigations are missing. Herein, the resistivity -- strain behavior in terms of stability and sensitivity of CPCs based on poly(styrene-butadiene-styrene) (SBS) containing multiwalled carbon nanotubes (MWCNTs) are studied. It is demonstrated that the preparation method has an important influence on the resistivity -- strain behavior of these CPCs. Under linear uniaxial strain, the sensitivity increases with decreasing filler content for both composites, showing higher strain sensitivity near the percolation threshold. Moreover, a higher and wider range of sensitivities is obtained for SBS/MWCNT composites from melt mixing. Under dynamic strain, resistivity downward drifting and shoulder peaks are shown for composites from melt mixing, while linear relationships and reversible resistivity in every cycle are observed for composites from solution mixing, showing good electromechanical consistency, stability and durability. From the TEM, rheology, SEM, SAXS, Raman microscopy and analytical modeling studies, the difference in morphology is thought to be responsible for such resistivity -- strain behavior. As more disordered and less densely packed conductive networks in melt-mixed CPCs are more easily destroyed under strain, evenly distributed and densely packed networks in solution mixed CPCs are more stable during cyclic stretching. Finally, human knee motions have been detected using these CPCs, demonstrating a potential application of these CPCs as movement sensors. [ABSTRACT FROM AUTHOR]

The resistivity-strain behavior of conductive polymer composites (CPCs) has gained intense interest due to its importance for various applications. The resistivity of CPCs often increases substantially and linearly under strain. To achieve constant resistivity under strain, a large filler content and special network configuration are often required. And a tunable step-wise resistivity-strain behavior has yet to be reported. Herein, a new method combining polymer blends and pre-stretching is introduced to modify the resistivity-strain behavior of CPCs based on thermoplastic polyurethane (TPU)/polyolefin elastomer (POE) with multi-walled carbon nanotubes (MWCNTs) selectively incorporated in the TPU phase. Depending on the compositions of blends and the intensity of pre-stretching, various interesting resistivity-strain behaviors have been achieved. The resistivity can be either linearly increasing or constant. Interestingly, two-stepwise resistivity-strain behavior has been achieved, with first an increase then a constant value. To understand this unique phenomenon, the phase morphology and conductive network structure are systematically characterized. It is observed that the orientation of MWCNTs is strongly correlated with overall resistivity. Finally, a mechanism involving fibrillization and "slippage" between conductive phases is proposed to explain the resistivity-strain dependency. This study provides guidelines for the preparation of high performance strain sensors as well as stretchable conductors. [ABSTRACT FROM AUTHOR]

A novel integrated strategy is proposed to construct the LiNi 0.9 Co 0.09 W 0.01 O 2 with simultaneous spinel phase and Li 2 TiO 3 conductive network, which can enhance the lithium-ion migration kinetics and structural stability of ultrahigh-Ni cathode materials. [Display omitted] The tungsten with high oxidation states (W6+) had been proved to effectively improve the electrochemical performance of ultrahigh-nickel (Ni ≥ 90 %) cathode materials due to the unique microstructures. However, the exat location and underlying action mechanism of tungsten are still not well-understood, and there have been no reports on in-situ modification from bulk to surface simultaneously for these novel cathode materials. Here, a novel integrated strategy is proposed for in-situ modification of LiNi 0.9 Co 0.09 W 0.01 O 2 (NCW). Innovatively, the introduction of nano spinel phase and titanium pinned into the lattice further suppresses the anisotropic variation of unit cell and promotes the lithium-ion migration kinetics within the bulk. Additionally, the Li 2 TiO 3 conductive network enhances migration kinetics across interface and protects the active material against electrolyte erosion. Furthermore, the combination of in-situ analysis and DFT calculation reveals the ordered distribution of tungsten and the suppression effects of titanium on phase transition and cobalt redox. Consequently, the titanium-modified NCW exhibits significantly improved electrochemical performance, such as capacity retention of 93.0 % at 1C after 500 cycles in pouch-type full-cell, along with stable lattice oxygen during operation. [ABSTRACT FROM AUTHOR]

To understand how the thermal conductivity (TC) of virgin commercial polymers and their composites with low graphite filler amounts can be improved, the effect of material choice, annealing and moisture content is investigated, all with feasible industrial applicability in mind focusing on injection molding. Comparison of commercial HDPE, PP, PLA, ABS, PS, and PA6 based composites under conditions minimizing the effect of the skin-core layer (measurement at half the sample thickness) allows to deduce that at 20 m% of filler, both the (overall) in- and through-plane TC can be significantly improved. The most promising results are for HDPE and PA6 (through/in-plane TC near 0.7/4.3 W·m−1K−1 for HDPE and 0.47/4.3 W·m−1K−1 for PA6 or an increase of 50/825% and 45/1200% respectively, compared to the virgin polymer). Testing with annealed and nucleated PA6 and PLA samples shows that further increasing the crystallinity has a limited effect. A variation of the average molar mass and moisture content is also almost without impact. Intriguingly, the variation of the measuring depth allows to control the relative importance of the TC of the core and skin layer. An increased measurement depth, hence, a higher core-to-skin ratio measurement specifically indicates a clear increase in the through-plane TC (e.g., factor 2). Therefore, for basic shapes, the removal of the skin layer is recommendable to increase the TC. [ABSTRACT FROM AUTHOR]

Dual CEI/SEI protection layers formed by an inducing strategy are successfully realized for optimizing the stability of electrolyte/electrode interfaces and further improving the rate performance and cycling stability of SSLMBs. [Display omitted] Designing a robust cathode electrolyte interphase (CEI) on a high-voltage cathode and stable solid electrolyte interphase (SEI) on a Li anode is the key to success in developing solid-state Li metal batteries (SSLMBs). In this work, we design an inorganic compound-intensive CEI layer and a LiF-rich gradient SEI layer in SSLMBs through the in-situ polymerization of a novel multi-functional electrolyte. The inorganic compound-intensive CEI offers excellent electrochemical compatibility with high-voltage layered cathode LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM), while the LiF-rich gradient SEI successfully suppresses Li dendrite formation and harmful interfacial parasite reactions. As a result, SSLMBs present a remarkable rate performance of 182 mAh g−1 at 1 C and a long cycling stability of 88.6% capacity retention after 300 cycles at room temperature. The fundamental insights into interface chemistry and facile strategy demonstrated in this work could assist the rapid development of SSLMBs toward remarkable performance. [ABSTRACT FROM AUTHOR]

Background: Realgar, a Chinese herbal decoction, has been used to treat various types of tumors with positive outcomes; however, there is a lack of convincing evidence on its use for the treatment of esophageal cancer (EC). In this study, the role of the p62-Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in the regulation of EC cell proliferation, migration, and ferroptosis in response to realgar was assessed., Methods: Different concentrations of realgar (0, 10, 20, 40, 60, 80, and 100 μmol/L) were applied to the EC cell lines Eca109 and KYSE150. The inhibition rate and half-inhibitory concentration (IC 50 ) were determined using the Cell Counting Kit-8 (CCK-8) method. Subsequently, the cells were treated with realgar (1/2IC 50 , IC 50 , 2IC 50 ). Cell migration was measured using the scratch assay, and cell invasion was measured using the transwell assay. The mRNA expression of p62, Keap1, and Nrf2 was measured by quantitative real-time polymerase chain reaction (qRT-PCR), and the protein expression of p62, Keap1, Nrf2, matrix metalloproteinase (MMP)-2, MMP-9, E-cadherin, Slug, N-cadherin, and vimentin was measured by Western blot. The control, 2IC 50 , shRNA-NC, shRNA-p62, 2IC 50 + shRNA-NC, 2IC 50 + shRNA-p62, shRNA-Keap1, 2IC 50 + shRNA-Keap1, and 2IC 50 + shRNA-p62 + shRNA-Keap1 groups were defined. The CCK-8 method was used to measure the cell inhibition rate, and the clone formation assay was used to measure the clone formation ability. Moreover, the scratch assay was used to detect the cell migration ability, and the transwell assay was used to detect the cell invasion ability. Transmission electron microscopy was used to observe the mitochondrial morphology, Prussian blue staining was used to observe the intracellular iron particle distribution, and flow cytometry was used to detect changes in intracellular reactive oxygen species. In addition, qRT-PCR was performed to detect p62, Keap1, Nrf2, and glutathione peroxidase 4 (GPX4) mRNA expression, and Western blot was performed to detect p62, Keap1, Nrf2, E-cadherin, Slug, N-cadherin, and GPX4 protein expression., Results: Realgar inhibited Eca109 and KYSE150 cell proliferation in a time- and concentrationdependent manner. It also significantly inhibited the migration and invasion of Eca109 and KYSE150 cells and affected the mRNA and protein expression of p62, Keap1, and Nrf2. In response to realgar, low p62 expression inhibited the proliferation, migration, and invasion of Eca109 and KYSE150 cells, as well as ferroptosis induction., Conclusion: The findings demonstrate that inhibiting the p62-Keap1-Nrf2 signaling pathway promotes the inhibitory effects of realgar on EC cells., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Lithium-sulfur (Li-S) batteries stand out for their high theoretical specific capacity and cost-effectiveness. However, the practical implementation of Li-S batteries is hindered by issues such as the shuttle effect, tardy redox kinetics, and dendrite growth. Herein, an appealingly designed covalent organic framework (COF) with bi-functional active sites of cyanide groups and polysulfide chains (COF-CN-S) is developed as cooperative functional promoters to simultaneously address dendrites and shuttle effect issues. Combining in situ techniques and theoretical calculations, it can be demonstrated that the unique chemical architecture of COF-CN-S is capable of performing the following functions: 1) The COF-CN-S delivers significantly enhanced Li + transport capability due to abundant ion-hopping sites (cyano-groups); 2) it functions as a selective ion sieve by regulating the dynamic behavior of polysulfide anions and Li + , thus inhibiting shuttle effect and dendrite growth; 3) by acting as a redox mediator, the COF-CN-S can effectively control the electrochemical behavior of polysulfides and enhance their conversion kinetics. Based on the above advantages, the COF-CN-S endows Li-S batteries with excellent performance. This study highlights the significance of interface modification and offers novel insights into the rational design of organic materials in the Li-S realm., (© 2023 Wiley-VCH GmbH.)

Although the serum-abundant metal-binding protein transferrin (encoded by the Trf gene) is synthesized primarily in the liver, its function in the liver is largely unknown. Here, we generated hepatocyte-specific Trf knockout mice (Trf-LKO), which are viable and fertile but have impaired erythropoiesis and altered iron metabolism. Moreover, feeding Trf-LKO mice a high-iron diet increased their susceptibility to developing ferroptosis-induced liver fibrosis. Importantly, we found that treating Trf-LKO mice with the ferroptosis inhibitor ferrostatin-1 potently rescued liver fibrosis induced by either high dietary iron or carbon tetrachloride (CCl4) injections. In addition, deleting hepatic Slc39a14 expression in Trf-LKO mice significantly reduced hepatic iron accumulation, thereby reducing ferroptosis-mediated liver fibrosis induced by either a high-iron diet or CCl4 injections. Finally, we found that patients with liver cirrhosis have significantly lower levels of serum transferrin and hepatic transferrin, as well as higher levels of hepatic iron and lipid peroxidation, compared with healthy control subjects. Taken together, these data indicate that hepatic transferrin plays a protective role in maintaining liver function, providing a possible therapeutic target for preventing ferroptosis-induced liver fibrosis., (© 2020 by The American Society of Hematology.)

Highly sensitive conductive polymer composites (CPCs) are designed employing a facile and low-cost extrusion manufacturing process for both low- and high-strain sensing in the field of, for example, structural health/damage monitoring and human body movement tracking. Focus is on the morphology control for extrusion-processed carbon black (CB)-filled CPCs, utilizing binary and ternary composites based on thermoplastic polyurethane (TPU) and olefin block copolymer (OBC). The relevance of the correct CB amount, kinetic control through a variation of the compounding sequence, and thermodynamic control induced by annealing is highlighted, considering a wide range of experimental (e.g., static and dynamic resistance/scanning electron microscopy/rheological measurements) and theoretical analyses. High CB mass fractions (20 m %) are needed for OBC (or TPU)-CB binary composites but only lead to an intermediate sensitivity as their conductive network is fully packed and therefore difficult to be truly destructed. Annealing is needed to enable a monotonic increase of the relative resistance with respect to strain. With ternary composites, a much higher sensitivity with a clearer monotonic increase results, provided that a low CB mass fraction (10-16 m %) is used and annealing is applied. In particular, with CB first dispersed in OBC and annealing, a less compact, hence, brittle conductive network (10-12 m % CB) is obtained, allowing high-performance sensing.