A solution-to-solid conversion chemistry enables ultrafast-charging and long-lived molten salt aluminium batteries.

Conventional solid-to-solid conversion-type cathodes in batteries suffer from poor diffusion/reaction kinetics, large volume changes and aggressive structural degradation, particularly for rechargeable aluminium batteries (RABs). Here we report a class of high-capacity redox couples featuring a solution-to-solid conversion chemistry with well-manipulated solubility as cathodes-uniquely allowed by using molten salt electrolytes-that enable fast-charging and long-lived RABs. As a proof-of-concept, we demonstrate a highly reversible redox couple-the highly soluble InCl and the sparingly soluble InCl3-that exhibits a high capacity of about 327 mAh g-1 with negligible cell overpotential of only 35 mV at 1 C rate and 150 °C. The cells show almost no capacity fade over 500 cycles at a 20 C charging rate and can sustain 100 mAh g-1 at 50 C. The fast oxidation kinetics of the solution phase upon initiating the charge enables the cell with ultrafast charging capability, whereas the structure self-healing via re-forming the solution phase at the end of discharge endows the long-term cycling stability. This solution-to-solid mechanism will unlock more multivalent battery cathodes that are attractive in cost but plagued by poor reaction kinetics and short cycle life.

Insight into the role of crystallinity in oxide electrolytes enabling high-performance all-solid-state lithium-sulfur batteries.

All-solid-state lithium-sulfur batteries (ASSLSBs) would be a promising candidate for the next-generation batteries due to the utilization of energy-dense electrodes and the non-flammable oxide solid-state electrolytes (SSEs), but still face great challenges such as low ionic conductivity of SSEs, poor interfacial contact and lithium (Li) dendrite propagation. Herein, we regulated the crystallinity degrees of the large-scale-fabricated Li1.5Al0.5Ge1.5(PO4)3 (LAGP) SSEs and explored the critical role of crystallinity optimization in reinforcing the basic properties of LAGP, developing a fundamental explanation for the inherent relation between the crystallinity and the performance of ASSLSBs. Benefiting from the optimized crystallinity (∼99.9 %), the large-scale-fabricated LAGP not only realizes the low surface roughness and high ionic conductivity (2.11 × 10-4 S cm-1) to improve interfacial contact and reduce resistance in ASSLSBs, but also possesses the dense internal structure with low porosity (1.49 %) to physically resist dendritic propagation and penetration. Consequently, the ASSLSB with the optimized LAGP delivers a high reversible capacity of 647.9 mAh/g even after 150 cycles at 0.1 C. This work confirms the significance of crystallinity in understanding the working mechanisms of oxide SSEs and developing future high-performance ASSLSBs.

Water-Lubricated Aluminum Vanadate for Enhanced Rechargeable Magnesium Ion Storage.

Magnesium ion batteries (MIBs) have attracted much attention due to their low cost and high safety properties. However, the intense charge repulsion effect and sluggish diffusion dynamics of Mg2+ ions result in unsatisfactory electrochemical performance of conventional cathode materials in MIBs. This work reports water-lubricated aluminum vanadate (HAlVO) as high-performance cathode material for Mg2+ ions storage and investigates the capacity fade mechanism of water-free aluminum vanadate (AlVO). The charge density difference based on density functional theory calculation is performed to analyze the charge transfer process of water-lubricated/free aluminum vanadates (HAlVO/AlVO). The different charge transfer phenomena of two materials and the charge shielding effect of water molecule in HAlVO are revealed. Moreover, the single-phase structural evolution process and the Mg2+ ions storage mechanism of HAlVO are further investigated deeply by different in situ and ex situ characterization methods. This work proves that HAlVO is a potential candidate cathode material to satisfy the high-performance reversible Mg2+ ions storage, and the water-lubricated method is an effective strategy to improve the electrochemical performance of vanadium oxides cathode.

Xenon Ion Implantation Induced Surface Compressive Stress for Preventing Dendrite Penetration in Solid-State Electrolytes.

Solid-state electrolytes (SSEs) have been thrust into the limelight for the revival of energy-dense lithium metal batteries, but still face the challenge of failure caused by the dendrite penetration. Mounting evidence indicates that dendrite penetration is related to the mechanical failure in SSEs, which calls for mechanical engineering to tackle this problem. This work reports a proof of concept that ion implantation induced surface compressive stress enables resistance in the dendrite penetration. A deterministic sequential multiple ion energies implantation is used to generate compressive stress, with implanted Xe ions distributed in a range of 160-600 Å from the surface. The symmetric lithium cells show that pellets with an implantation dose of 1013 Xe cm-2 exhibit stable stripping/plating cycles and extended lifespan, while a lower dose of 1012 Xe cm-2 cannot create sufficient stress to prevent dendrite penetration, and an excessive dose of 1014 Xe cm-2 leads to structural destruction and a decrease in stress. This improved performance is attributed to the induced surface compressive stress balanced over crystal grains, which is confirmed by grazing incidence diffraction techniques. The author's efforts demonstrate the usefulness of surface compressive stress to suppress dendrite penetration, offering more insight into rational stress-strain engineering as opposed to empirical optimization.

Highly Crystallized Prussian Blue with Enhanced Kinetics for Highly Efficient Sodium Storage.

Prussian blue analogs (PBAs) featuring large interstitial voids and rigid structures are broadly recognized as promising cathode materials for sodium-ion batteries. Nevertheless, the conventionally prepared PBAs inevitably suffer from inferior crystallinity and lattice defects, leading to low specific capacity, poor rate capability, and unsatisfied long-term stability. As the Na+ migration within PBAs is directly dependent on the periodic lattice arrangement, it is of essential significance to improve the crystallinity of PBAs and hence ensure long-range lattice periodicity. Herein, a chemical inhibition strategy is developed to prepare a highly crystallized Prussian blue (Na2Fe4[Fe(CN)6]3), which displays an outstanding rate performance (78 mAh g-1 at 100 C) and long life-span properties (62% capacity retention after 2000 cycles) in sodium storage. Experimental results and kinetic analyses demonstrate the efficient electron transfer and smooth ion diffusion within the bulk phase of highly crystallized Prussian blue. Moreover, in situ X-ray diffraction and in situ Raman spectroscopy results demonstrate the robust crystalline framework and reversible phase transformation between cubic and rhombohedral within the charge-discharge process. This research provides an innovative way to optimize PBAs for advanced rechargeable batteries from the perspective of crystallinity.

8­Gingerol regulates colorectal cancer cell proliferation and migration through the EGFR/STAT/ERK pathway.

8­Gingerol, which is extracted from ginger (Zingiber officinale Roscoe), has been shown to possess antioxidant and anti­inflammatory properties. However, the antitumor effect of 8­gingerol has not been fully elucidated. The aim of the present study was to investigate the therapeutic potential of 8­gingerol against colorectal cancer (CRC). The results demonstrated that 8­gingerol significantly inhibited cell proliferation in CRC cell models. Treatment of CRC cells with 8­gingerol resulted in dose­dependent decreases in migration and invasion. The inhibitory effect of 8­gingerol on CRC cell growth was attributed to cell cycle arrest and increased apoptosis. Moreover, to the best of our knowledge, the present study was the first to demonstrate that 8­gingerol acted as an inhibitor of epidermal growth factor receptor (EGFR) signaling. 8­Gingerol inhibited CRC cell proliferation and migration by targeting the EGFR/signal transducer and activator of transcription/extracellular signal­regulated kinase pathway, and the effects of 8­gingerol depended on the expression of EGFR. Moreover, 8­gingerol reduced the effective dosage of 5­fluorouracil and, thereby, the toxicity of drug combination therapy. These data suggest that 8­gingerol may be a promising candidate for the development of novel anticancer agents against CRC.

Polyol Solvation Effect on Tuning the Universal Growth of Binary Metal Oxide Nanodots@Graphene Oxide Heterostructures for Electrochemical Applications.

Tuning the uniformity and size of binary metal oxide nanodots on graphene oxide (BMO NDs@GO) is significant but full of challenges in wet-chemistry, owing to the difficulties of controlling the complicated cation/anion co-adsorption, heterogeneous nucleation, and overgrowth processes. Herein, the aim is to tune these processes by understanding the functions of various alcohol solvents for NDs growth on GO. It is found that the polyol solvation effect is beneficial for obtaining highly uniform BMO NDs@GO. Polyol shell capped metal ions exhibit stronger hydrogen-bond interactions with the GO surface, leading to a uniform cation/anion co-adsorption and followed heterogeneous nucleation. The polyol-solvated ions with large diffusion energy barrier drastically limit the ion diffusion kinetics in liquids and at the solid/liquid interface, resulting in a slow and controllable growth. Moreover, the synthesis in polyol systems is highly controllable and universal, thus eleven BMO and polynary metal oxide NDs@GO are obtained by this method. The synthetic strategy provides improved prospects for the manufacture of inorganic NDs and their expanding electrochemical applications.

Hierarchical Mn3O4/Graphene Microflowers Fabricated via a Selective Dissolution Strategy for Alkali-Metal-Ion Storage.

Mn3O4 is a potential anode for alkali-metal (Li/Na/K)-ion batteries because of the high capacity, abundant resources, and eco-friendliness. However, its ion storage performance is limited by poor electronic conductivity and large volume expansion during the charging/discharging process. In this study, we presented a facile dissolution strategy to fabricate ultrathin nanosheet-assembled hierarchical Mn3O4/graphene microflowers, realizing enhanced alkali-metal-ion storage performance. The synthetic mechanism was proven as the selective dissolution of vanadium via controlled experiments with different reaction times. The as-synthesized composites showed high lithium storage capacity (about 900 mA h g-1) and superior cyclability (∼400 mA h g-1 after 500 cycles). In addition, when evaluated as a Na-ion battery anode, the reversible capacity of about 200 mA h g-1 was attained, which remained at 167 mA h g-1 after 200 cycles. Moreover, to the best of our knowledge, the potassium storage properties of Mn3O4 were evaluated for the first time and a reversible capacity of about 230 mA h g-1 was achieved. We believe that our findings will be instructive for future investigations of high-capacity anode materials for alkali-metal-ion batteries.

Nonhierarchical Heterostructured Fe2 O3 /Mn2 O3 Porous Hollow Spheres for Enhanced Lithium Storage.

High capacity transition-metal oxides play significant roles as battery anodes benefiting from their tunable redox chemistry, low cost, and environmental friendliness. However, the application of these conversion-type electrodes is hampered by inherent large volume variation and poor kinetics. Here, a binary metal oxide prototype, denoted as nonhierarchical heterostructured Fe2 O3 /Mn2 O3 porous hollow spheres, is proposed through a one-pot self-assembly method. Beyond conventional heteromaterial, Fe2 O3 /Mn2 O3 based on the interface of (104)Fe2O3 and (222)Mn2O3 exhibits the nonhierarchical configuration, where nanosized building blocks are integrated into microsized spheres, leading to the enhanced structural stability and boosted reaction kinetics. With this design, the Fe2 O3 /Mn2 O3 anode shows a high reversible capacity of 1075 mA h g-1 at 0.5 A g-1 , an outstanding rate capability of 638 mA h g-1 at 8 A g-1 , and an excellent cyclability with a capacity retention of 89.3% after 600 cycles.

3.0 V High Energy Density Symmetric Sodium-Ion Battery: Na4V2(PO4)3∥Na3V2(PO4)3.

Symmetric sodium-ion batteries (SIBs) are considered as promising candidates for large-scale energy storage owing to the simplified manufacture and wide abundance of sodium resources. However, most symmetric SIBs suffer from suppressed energy density. Here, a superior congeneric Na4V2(PO4)3 anode is synthesized via electrochemical preintercalation, and a high energy density symmetric SIB (Na3V2(PO4)3 as a cathode and Na4V2(PO4)3 as an anode) based on the deepened redox couple of V4+/V2+ is built for the first time. When measured in half cell, both electrodes show stabilized electrochemical performance (over 3000 cycles). The symmetric SIBs exhibit an output voltage of 3.0 V and a cell-level energy density of 138 W h kg-1. Furthermore, the sodium storage mechanism under the expanded measurement range of 0.01-3.9 V is disclosed through an in situ X-ray diffraction technique.