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The irreversible deterioration of electrochemical performance in Ni‐rich cathode materials, attributed to crack propagation and undesired side reactions, poses a critical barrier to the further development of high‐energy power batteries for electrical vehicles (EVs). Herein, a concentration gradient strategy is proposed for synthesizing a Ni‐rich cathode with enhanced mechanical and electrochemical stability to address the issues related to the irreversible structural deterioration. Notably, the concentration gradient structure contributes to superior mechanical strength in secondary particles due to the radially orientated primary particles resulted from Mn composition grading, which effectively alleviate the internal strain caused by structural changes and fatigue destruction during successive cycling. Moreover, the Mn‐rich surface minimizes the parasitic side reactions at the electrode–electrolyte interface. Benefitting from the above, the concentration gradient sample can deliver ≈180.1 mA h g−1 at 1 C and retain 96.2% of its initial discharge capacity after 100 cycles. This work demonstrates that the concentration gradient structure can simultaneously improve the mechanical and chemical stabilities of Ni‐rich cathode and offers a feasible way for designing stable lithium‐ion batteries with high energy density. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium batteries (ASSLBs) based on sulfide solid electrolytes (SEs) are one of the most promising strategies for next‐generation energy storage systems and electronic devices. However, the poor chemical/electrochemical stability of sulfide SEs with oxide cathode materials and high interfacial impedance, particularly due to physical contact failure, are the major limiting factors to the development of sulfide SEs in ASSLBs. Herein, the composite cathode of MOF‐derived Fe7S8@C and Li6PS5Br fabricated by an infiltration method (IN–Fe7S8) with dissoluble sulfide electrolyte (dissoluble SE) is reported. Dissoluble SE can easily infiltrate the porous sheet‐type Fe7S8@C cathode to homogeneously contact with Fe7S8 nanoparticles that are embedded in the surrounding carbon matrixes and form a fast ionic transport network. Benefiting from applying dissoluble SE and Fe7S8@C, the IN‐Fe7S8‐based cells displayed a reversible capacity of 510 mAh g−1 after 180 cycles at 0.045 mA cm−2 at 30 °C. This work demonstrates a novel and practical method for the development of high‐performance all‐sulfide‐based solid state batteries. [ABSTRACT FROM AUTHOR]

The deployment of lithium metal anode in solid‐state batteries with polymer electrolytes has been recognized as a promising approach to achieving high‐energy‐density technologies. However, the practical application of the polymer electrolytes is currently constrained by various challenges, including low ionic conductivity, inadequate electrochemical window, and poor interface stability. To address these issues, a novel eutectic‐based polymer electrolyte consisting of succinonitrile (SN) and poly (ethylene glycol) methyl ether acrylate (PEGMEA) is developed. The research results demonstrate that the interactions between SN and PEGMEA promote the dissociation of the lithium difluoro(oxalato) borate (LiDFOB) salt and increase the concentration of free Li+. The well‐designed eutectic‐based PAN1.2‐SPE (PEGMEA: SN=1: 1.2 mass ratio) exhibits high ionic conductivity of 1.30 mS cm−1 at 30 °C and superior interface stability with Li anode. The Li/Li symmetric cell based on PAN1.2‐SPE enables long‐term plating/stripping at 0.3 and 0.5 mA cm−2, and the Li/LiFePO4 cell achieves superior long‐term cycling stability (capacity retention of 80.3 % after 1500 cycles). Moreover, Li/LiFePO4 and Li/LiNi0.6Co0.2Mn0.2O2 pouch cells employing PAN1.2‐SPE demonstrate excellent cycling and safety characteristics. This study presents a new pathway for designing high‐performance polymer electrolytes and promotes the practical application of high‐stable lithium metal batteries. [ABSTRACT FROM AUTHOR]

Co shows excellent performance in the high voltage range for layered oxide cathode materials for sodium ion batteries (SIBs). However, its high cost and toxicity are significant disadvantages.Co‐free cathodes with high performance are urgently needed for development. Herein, cheap Mg and Ti elements are preferred to replace Co elements. A P2‐Na0.67Mn0.53Ni0.30Mg0.085Ti0.085O2 (Ni30MgTi) cathode shows a high reversible specific capacity of 118 mA h g−1 at a current density of 50 mA g−1 in 2.0–4.25 V, which is even higher than that in the base sample with Co. Moreover, Mg and Ti raise the median discharge voltage from 3.21 to 3.59 V, which raises the energy density from 325 to 410 Wh kg−1. On the other hand, ex situ XPS and in situ differential electrochemical mass spectrometry tests indicate that Ni30MgTi has a stable anionic redox reaction with reversible capacity in the high voltage range. The concept of bimetallic co‐substitution offers a simple and effective Co‐free strategy to reduce the cost and increase the energy density of layered oxide cathode materials simultaneously for SIBs. [ABSTRACT FROM AUTHOR]

Secondary batteries have been widespread in the daily life causing an ever-growing demand for long-cycle lifespan and high-energy alkali-ion batteries. As an essential constituent part, electrode materials with superior electrochemical properties play a vital role in the battery systems. Here, an outstanding electrode of yolk-shell ZnS@C nanorods is developed, introducing considerable void space via a self-sacrificial template method. Such carbon encapsulated nanorods moderate integral electronic conductivity, thus ensuring rapid alkali-ions/electrons transporting. Furthermore, the porous structure of these nanorods endows enough void space to mitigate volume stress caused by the insertion/extraction of alkali-ions. Due to the unique structure, these yolk-shell ZnS@C nanorods achieve superior rate performance and cycling performance (740 mAh g-1 at 1.0 A g-1 after 540 cycles) for lithium-ion batteries. As a potassium-ion batteries anode, they achieve an ultra-long lifespan delivering 211.1 mAh g-1 at 1.0 A g-1 after 5700 cycles. The kinetic analysis reveals that these ZnS@C nanorods with considerable pseudocapacitive contribution benefit the fast lithiation/delithiation. Detailed transmission electron microscopy (TEM) and X-ray diffraction (XRD) analyses indicate that such yolk-shell ZnS@C anode is a typical reversible conversion reaction mechanism accomplished by alloying processes. This rational design strategy opens a window for the development of superior energy storage materials. [ABSTRACT FROM AUTHOR]

Solid‐state lithium metal batteries (SLMBs) are attracting enormous attention due to their enhanced safety and high theoretical energy density. However, the alkali lithium with high reducibility can react with the solid‐state electrolytes resulting in the inferior cycle lifespan. Herein, inspired by the idea of interface design, the 1‐butyl‐1‐methylpyrrolidinium bis(trifluoromethanesulfonyl) imide as an initiator to generate an artificial protective layer in polymer electrolyte is selected. Time‐of‐flight secondary ion mass spectrometry and X‐ray photoelectron spectroscopy reveal the stable solid electrolyte interface (SEI) is in situ formed between the electrolyte/Li interface. Scanning electron microscopy (SEM) images demonstrate that the constructed SEI can promote homogeneous Li deposition. As a result, the Li/Li symmetrical cells enable stable cycle ultralong‐term for over 4500 h. Moreover, the as‐prepared LiFePO4/Li SLMBs exhibit an impressive ultra‐long cycle lifespan over 1300 cycles at 1 C, as well as 1600 cycles at 0.5 C with a capacity retention ratio over 80%. This work offers an effective strategy for the construction of the stable electrolyte/Li interface, paving the way for the rapid development of long lifespan SLMBs. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) have attracted much attention due to their abundance, easy accessibility, and low cost. P2‐type layered oxide materials, as one of the most potential cathode candidates for SIBs, have been widely studied. However, various kinds of structural evolution during cycling are harmful to the stability. In the present Minireview, the phase transitions occurring in the process of charge/discharge are summarized, and the mechanism of structural rearrangement and phase transition are introduced. This Minireview is aimed at helping researchers understand the detailed structural evolution, and propose strategies of designing the P2‐type layered oxide cathodes with low strain. [ABSTRACT FROM AUTHOR]

For the past few years, a new generation of energy storage systems with large theoretical specific capacity has been urgently needed because of the rapid development of society. Lithium–sulfur (Li−S) batteries are regarded as one of the most promising candidates for novel battery systems, since their resurgence at the end of the 20th century Li−S batteries have attracted ever more attention, attributed to their notably high theoretical energy density of 2600 W h kg−1, which is almost five times larger than that of commercial lithium‐ion batteries (LIBs). One of the determining factors in Li−S batteries is how to design/prepare the sulfur cathode. For the sulfur host, the major technical challenge is avoiding the shuttling effect that is caused by soluble polysulfides during the reaction. In past decades, though the sulfur cathode has developed greatly, there are still some enormous challenges to be conquered, such as low utilization of S, rapid decay of capacity, and poor cycle life. This article spotlights the recent progress and foremost findings in improving the performance of Li−S batteries by employing multifunctional metal phosphides as host materials. The current state of development of the sulfur electrode of Li−S batteries is summarized by emphasizing the relationship between the essential properties of metal phosphide‐based hybrid nanomaterials, the chemical reaction with lithium polysulfides and the latter′s influence on electrochemical performance. Finally, trends in the development and practical application of Li−S batteries are also pointed out. [ABSTRACT FROM AUTHOR]

Most P2‐type layered oxides exhibit a large volume change when they are charged into high voltage, and it further leads to bad structural stability. In fact, high voltage is not the reason which causes the irreversible phase transition. There are two internal factors which affect structural evolution: the amount and distribution of Na ions retained in the lattice. Hereon, a series of layered oxides Na2/3MnxNix−1/3Co4/3−2xO2 (1/3≤x≤2/3) were synthesized. It is observed that different components have different structural evolutions during the charge/discharge processes, and further researches find that the distribution of Na ions in layers is the main factor. By controlling the distribution of Na ions, the phase transition process can be well controlled. As the referential component, P2‐Na2/3Mn1/2Ni1/6Co1/3O2 cathode with uniform distribution of Na ions is cycled at the voltage window of 1.5–4.5 V, which exhibits a volume change as low as 1.9 %. Such a low strain is beneficial for cycling stability. The current work provides a new and effective route to regulate the structural evolution of the promising P2‐type layered cathode for sodium ion batteries. [ABSTRACT FROM AUTHOR]

Most P2‐type layered oxides exhibit a large volume change when they are charged into high voltage, and it further leads to bad structural stability. In fact, high voltage is not the reason which causes the irreversible phase transition. There are two internal factors which affect structural evolution: the amount and distribution of Na ions retained in the lattice. Hereon, a series of layered oxides Na2/3MnxNix−1/3Co4/3−2xO2 (1/3≤x≤2/3) were synthesized. It is observed that different components have different structural evolutions during the charge/discharge processes, and further researches find that the distribution of Na ions in layers is the main factor. By controlling the distribution of Na ions, the phase transition process can be well controlled. As the referential component, P2‐Na2/3Mn1/2Ni1/6Co1/3O2 cathode with uniform distribution of Na ions is cycled at the voltage window of 1.5–4.5 V, which exhibits a volume change as low as 1.9 %. Such a low strain is beneficial for cycling stability. The current work provides a new and effective route to regulate the structural evolution of the promising P2‐type layered cathode for sodium ion batteries. [ABSTRACT FROM AUTHOR]

Most P2‐type layered oxides exhibit a large volume change when they are charged into high voltage, and it further leads to bad structural stability. In fact, high voltage is not the reason which causes the irreversible phase transition. There are two internal factors which affect structural evolution: the amount and distribution of Na ions retained in the lattice. Hereon, a series of layered oxides Na2/3MnxNix−1/3Co4/3−2xO2 (1/3≤x≤2/3) were synthesized. It is observed that different components have different structural evolutions during the charge/discharge processes, and further researches find that the distribution of Na ions in layers is the main factor. By controlling the distribution of Na ions, the phase transition process can be well controlled. As the referential component, P2‐Na2/3Mn1/2Ni1/6Co1/3O2 cathode with uniform distribution of Na ions is cycled at the voltage window of 1.5–4.5 V, which exhibits a volume change as low as 1.9 %. Such a low strain is beneficial for cycling stability. The current work provides a new and effective route to regulate the structural evolution of the promising P2‐type layered cathode for sodium ion batteries. [ABSTRACT FROM AUTHOR]

Most P2‐type layered oxides exhibit a large volume change when they are charged into high voltage, and it further leads to bad structural stability. In fact, high voltage is not the reason which causes the irreversible phase transition. There are two internal factors which affect structural evolution: the amount and distribution of Na ions retained in the lattice. Hereon, a series of layered oxides Na2/3MnxNix−1/3Co4/3−2xO2 (1/3≤x≤2/3) were synthesized. It is observed that different components have different structural evolutions during the charge/discharge processes, and further researches find that the distribution of Na ions in layers is the main factor. By controlling the distribution of Na ions, the phase transition process can be well controlled. As the referential component, P2‐Na2/3Mn1/2Ni1/6Co1/3O2 cathode with uniform distribution of Na ions is cycled at the voltage window of 1.5–4.5 V, which exhibits a volume change as low as 1.9 %. Such a low strain is beneficial for cycling stability. The current work provides a new and effective route to regulate the structural evolution of the promising P2‐type layered cathode for sodium ion batteries. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries have ultra–high energy density and are considered to be one of the most promising energy storage systems among all battery systems. However, due to various thorny problems, their commercial production has not yet been realized. The current experimental research normally lacks a systematic investigation into the conversion mechanism of the sulfur cathode from the electronic structure level. Actually, there is still a lack of powerful theoretical guidance for the design of high–performance Li–S batteries and the selection of modified materials still seems blind. In this article, with the chelated Fe‐polyvinyl pyrrolidone as the precursor, a series of Fe–based materials (e.g., Fe3O4@C, FeS@C, Fe3N@C) are synthesized as modified layers for battery separators, and the performance differences between them are systematically studied. It is found that the d–p band center model developed based on the d band center can reasonably combine the reaction potential of Li2S4 and performance differences. Simultaneously, the interaction between Li2S6 and the adsorption interface is simulated by ab initio molecular dynamics. This current work sheds light on promising material design for superior Li–S batteries both from a theoretical and experimental perspective. [ABSTRACT FROM AUTHOR]

As concerns about the safety of lithium‐ions batteries (LIBs) increases, aqueous zinc‐ion batteries (ZIBs) with a lower cost, higher safety, and higher co‐efficiency have attracted more and more interest. However, finding suitable cathode materials is still an urgent problem in ZIBs. In recent years, a lot of significant works have been reported, including manganese‐based cathodes, vanadium‐based cathodes, Prussian blue analog‐based materials, and sustainable quinone cathodes. In this review, some typical cathode materials are introduced. The detailed storage mechanisms and methods for improving the reaction kinetics of the zinc ions are summarized. Finally, the issues, challenges, and the research directions are provided. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) are the most promising candidates as alternatives to lithium‐ion batteries (LIBs), owing to the natural abundance of sodium salt and the low cost. However, the commercial application of SIBs is principally hampered by the absence of suitable cathode materials. Herein, a novel Na2FeP2O7@carbon/expanded graphite (NFPO@C/EG) composite with a unique microstructure was developed through a scalable sol‐gel process followed by a ball‐milling procedure with expanded graphite. Benefiting from the multiscale carbon‐modified structure, the NFPO@C/EG effectively improves the electronic conductivity and, at the same time, shortens the path of sodium ion transmission. As a consequence, the NFPO@C/EG cathode presents a much higher specific capacity and more stable cycling stability than NFPO@C and NFPO. The unique design of NFPO@C/EG endows a high ratio of pseudocapacitance contribution and a large Na+ diffusion coefficient. As a consequence, the NFPO@C/EG cathode displays stable cycle performance (82 mAh g−1 over 400 cycles at 232 mA g−1) and superior rate capability (60 mAh g−1 at a high charge/discharge density of 2320 mA g−1). This multiscale carbon‐modified design concept builds an avenue for the practical application of polyanionic cathode materials and promotes the development of low‐cost SIBs. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) have attracted much attention due to their abundance, easy accessibility, and low cost. All of these advantages make them potential candidates for large‐scale energy storage. The P2‐type layered transition‐metal oxides (NaxTMO2; TM=Mn, Co, Ni, Ti, Fe, V, Cr, and a mixture of multiple elements) exhibit good Na+ ion conductivity and structural stability, which make them an excellent choice for the cathode materials of SIBs. Herein, the structural evolution, anionic redox reaction, some challenges, and recent progress of NaxTMO2 cathodes for SIBs are reviewed and summarized. Moreover, a detailed understanding of the relationship of chemical components, structures, phase compositions, and electrochemical performance is presented. This Review aims to provide a reference for the development of P2‐type layered transition‐metal oxide cathode materials for SIBs. [ABSTRACT FROM AUTHOR]

Conventional lithium‐ion batteries, with flammable organic liquid electrolytes, have serious safety problems, which greatly limit their application. All‐solid‐state batteries (ASSBs) have received extensive attention from large‐scale energy‐storage fields, such as electric vehicles (EVs) and intelligent power grids, due to their benefits in safety, energy density, and thermostability. As the key component of ASSBs, solid electrolytes determine the properties of ASSBs. In past decades, various kinds of solid electrolytes, such as polymers and inorganic electrolytes, have been explored. Among these candidates, organic–inorganic composite solid electrolytes (CSEs) that integrate the advantages of these two different electrolytes have been regarded as promising electrolytes for high‐performance ASSBs, and extensive studies have been carried out. Herein, recent progress in organic–inorganic CSEs is summarized in terms of the inorganic component, electrochemical performance, effects of the inorganic ceramic nanostructure, and ionic conducting mechanism. Finally, the main challenges and perspectives of organic–inorganic CSEs are highlighted for future development. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fresh ginseng was buried in three types of sand with different moisture contents and three types of soil and then stored at 2 °C to determine the effects of these storage substrates on fresh ginseng. RESULTS: At a storage time of 200 days, ginseng stored in underforest soil softened the most slowly and had a significantly greater firmness compared to the other samples (P < 0.05). The amount of most ginsenosides changed after storage for most of the substrates. Samples stored in ginseng soil and biological fertilizer had the highest concentration of total saponin and ginseng polysaccharides, respectively. Fresh ginseng stored in medium‐water content sand had a significantly lower polyphenol oxidase activity (P < 0.05). A significant difference was observed in the total concentration of nucleosides and nucleobases between the ginseng samples stored with and without substrates (P < 0.05). CONCLUSION: The data obtained in the present study suggest that the use of storage substrates is an optimal method for extending the shelf life of fresh ginseng without detrimental effects on its components. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

As anode materials for high‐performance Li‐ion batteries, peapod‐like Ge‐based composites, including Ge, a Li‐inactive conducting Cu3Ge, and a porous carbon matrix are synthesized simply by annealing CuGeO3@dopamine in a H2/Ar atmosphere. The introduction of the carbon layer and inactive alloying phase Cu3Ge not only enhances the electrical conductivity of the Ge anode, but also reduces the volume change of Ge during the cell cycle as a buffer. In particular, the anode of this peapod‐like Cu3Ge/Ge@C shows an excellent long cycle life as well as outstanding capacity performance, with a discharge specific capacity up to 934 mA h g−1 after 500 cycles. [ABSTRACT FROM AUTHOR]

The practical application of all‐solid‐state lithium metal batteries (ASSLMBs) is limited by lithium (Li) anode instability including Li dendrite formation and deteriorating interface with electrolytes. Here, a functional additive, isosorbide mononitrate (ISMN) with a non‐resonant structure (O2−N−O−) is reported, which improves its reactivity and is utilized to build a stable N‐rich solid electrolyte interface, effectively alleviating Li dendrite and side reactions for poly(vinylidene fluoride) (PVDF)‐lithium bis(trifluoromethane sulfonyl) imide (LiTFSI)‐based electrolyte (PLE‐ISMN). In addition, the ion‐dipole interaction between ISMN and Li ions facilitates the dissociation of LiTFSI to form carrier ions, improving the ionic conductivity (4.4 × 10−4 S cm−1) and transference number (0.50) of PLE‐ISMN. Consequently, the Li/Li symmetric cell delivers a high critical current density of 2.0 mA cm−2 and stable Li stripping/plating cycling over 5000 h with a capacity of 1.0 mAh cm−2. Moreover, the Li|LiFePO4 cell delivers an excellent initial discharge capacity of 154.0 mAh g−1 with an outstanding capacity retention of 88.9% after 500 cycles at 0.5 C. The Li|LiNi0.8Co0.1Mn0.1O2 cell also exhibits a good cycling performance at 4.4 V at 1 C. [ABSTRACT FROM AUTHOR]

Amorphous nanoparticles of ZnO and TiO2 embedded in carbon nanocages (AZT⊂CNCs) were successfully synthesized through a simple annealing process of TiO2‐coated zeolitic imidazolate framework‐8 (ZIF‐8). In the current anode of AZT⊂CNCs, tiny ZnO and TiO2 nanoparticles were uniformly distributed in the carbon matrix (carbon nanocages), which could effectively buffer the volume expansion of electroactive ZnO and provide excellent electric conductivity. After fully investigating the electrochemical performance of the AZT⊂CNCs samples obtained with different additive amounts of tetrabutyl orthotitanate (TBOT) for TiO2 coating, it has been found that AZT‐30 (0.1 g ZIF‐8 with 30 mL TBOT) shows the best cycle stability (510 mA h g−1 after 350 cycles at 200 mA g−1) and a superior rate capability (610 mA h g−1 after 3500 cycles at 2 A g−1). The greatly enhanced Li‐ion storage performance could be ascribed to the fact that the introduction of amorphous TiO2 could activate the reversible lithiation/delithiation reaction of ZnO during the charge/discharge process. Dramatically enhanced: Amorphous nanoparticles of ZnO and TiO2 embedded in carbon nanocages (AZT⊂CNCs) were successfully synthesized by a simple annealing process of TiO2‐coated ZIF‐8 (see figure). As a Li‐ion battery anode, the hollow structure and porous carbon matrix make these materials useful. Moreover, with the addition of TiO2, the electrochemical reactions of the ZnO anode are greatly activated. [ABSTRACT FROM AUTHOR]

Abstract: The sulfur cathode, as a new generation of lithium‐ion battery cathode material, has a high theoretical energy density of about 2500 Wh kg−1. However, the low conductivity of sulfur and the “shuttle effect”, widely presenting in the lithiation/de‐lithiation process, seriously hinder its practical application. Here, we report a new nanoconfined oxidation route (first complete oxidation of metal sulfide and subsequently partial oxidation of the generated S from sulfide) for S cathode encapsulated with MnO2 nanosheets and N‐doped carbon hollow spheres. This nanoconfined oxidation route can successfully confine the sulfur particles in the interior of the carbon shell, and the rationally introduced nonpolar carbon and polar MnO2 can both reduce the dissolution of polysulfide during the charge‐discharge process. The obtained well‐defined S‐MnO2@C cathode exhibits high specific capacity with excellent cycling performance and superior rate capability. [ABSTRACT FROM AUTHOR]

Abstract: Three polyacetylenes were isolated and purified from Platycodon grandiflorum A. DC for the first time by high‐speed counter‐current chromatography using a two‐phase solvent system composed of hexane/ethyl acetate/methanol/water (1:31:1:31, v/v/v/v) and high‐performance liquid chromatography with an Agilent ZORBAX® SB‐C18 column (4.6 mm × 150 mm, 5 μm). After separation by high‐speed counter‐current chromatography and high‐performance liquid chromatography, we obtained 3.5 mg of platetyolin A, 4.1 mg of platetyolin B, and 18.1 mg of lobetyolin with purities of 97.2, 96.7, and 96.9%, respectively. The purity of each compound was assessed by high‐performance liquid chromatography and the chemical structures were evaluated by high‐resolution electrospray ionization time‐of‐flight mass spectrometry and one‐ and two‐dimensional NMR spectroscopy. Among the isolated compounds, platetyolin A and platetyolin B are newly reported compounds. [ABSTRACT FROM AUTHOR]

Mountain-cultivated ginseng ( MCG) can be considered a mimic of wild ginseng, whose seeds are sowed artificially, cultivated in the natural environment, and returned to the wild state before being used clinically. Cultivated ginseng ( CG) and MCG are mainly used as the commercial material for clinical applications. However, MCG is much more expensive but effective than CG. The aim of this study is to explore the differences in the pharmacokinetics and brain concentration of Rg1, Re, Rb1, and Rd after oral administration of MCG, CG, and pure ginsenosides. An ultra-performance liquid chromatography-tandem mass spectrometry method was developed and validated to determine the concentration of the four ginsenosides in rat plasma and brain tissue. Compared with the pure group, the area under the curve ( AUC) of all the four ginsenosides for CG and MCG increased. The mean brain concentrations of the four ginsenosides were found to be 10- to 15-fold lower than the corresponding contents in the plasma, and the poor permeability of ginsenosides into blood-brain barrier was indicated by the low concentrations of the four ginsenosides. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction Cynanchum bungei Decne (Baishouwu in China), is a famous traditional Chinese medicine that has been widely used as a tonic medicine or health food for centuries. Bungeiside-A, bungeiside-B and baishouwubenzophenone, as the major bioactive constituents in C. bungei, are challenging to separate and purify since bungeiside-A and -B are present in very low concentrations and have similar structures and high polarity. Objective To develop a method of isolation and purification of bungeiside-A and -B and baishouwubenzophenone from the Chinese medicinal plant Cynanchum bungei Decne by high-speed counter-current chromatography (HSCCC). Methodology The roots of C. bungei were extracted with light-petroleum (60-90 °C) and chloroform to remove the lipid substance. Then the residuals were extracted with methanol. The methanol extract was prepared for the subsequent HSCCC separation. The simple HSCCC method of separation and purification of bungeiside-A and -B and baishouwubenzophenone was established according to the solvent system, which was selected according to the measurement of partition coefficient ( K). The purities of target compounds were test by HPLC and the structure was identified by 1H NMR and 13C NMR. Results Bungeiside-A (9.4 mg), bungeiside-B (8.6 mg) and baishouwubenzophenone (5.7 mg) were obtained from 1.5 g of the methanol extract with purities of 93.2, 98.7 and 95.4%, respectively. Conclusion These results clearly demonstrate that HSCCC is a powerful tool for isolating and purifying components with similar structures, low concentration and high polarity from medicinal plant, such as bungeiside-A and -B and baishouwubenzophenone. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Keywords: Li-ion batteries; high-energy density; sulfur; metal phosphides EN Li-ion batteries high-energy density sulfur metal phosphides 1 1 1 09/28/21 20210924 NES 210924 In addition to avoiding the shuttling caused by soluble polysulfides, the design and preparation of sulfur cathodes for Li-S batteries must overcome challenges such as the low use of S, rapid decay of capacity and poor cycle life. This review spotlights recent progress in improving the performance of Li-S batteries by employing multifunctional metal phosphides as host materials. Frontispiece: Multifunctional Metal Phosphides as Superior Host Materials for Advanced Lithium-Sulfur Batteries. [Extracted from the article]

Keywords: aqueous batteries; cathode materials; manganese; quinone cathodes; storage mechanisms; vanadium; Zn-ion batteries EN aqueous batteries cathode materials manganese quinone cathodes storage mechanisms vanadium Zn-ion batteries 1 1 1 01/18/21 20210113 NES 210113 B Aqueous zinc ion batteries (ZIBs) b are the most promising rechargeable batteries for the grid energy storage and industrial energy storage for its lower cost and higher safety. The cathode materials consist of Mn-based materials, V-based materials, Prussian blue analogous (PBAs), Quinone and the others materials. Aqueous batteries, cathode materials, manganese, quinone cathodes, storage mechanisms, vanadium, Zn-ion batteries. [Extracted from the article]

Frontispiece: Recent Progress of P2-Type Layered Transition-Metal Oxide Cathodes for Sodium-Ion Batteries Keywords: electrochemistry; layered compounds; redox chemistry; sodium; transition metals EN electrochemistry layered compounds redox chemistry sodium transition metals 1 1 1 06/25/20 20200623 NES 200623 B In P2-type layered transition-metal oxides b , high capacity requires more Na ions to join in the transition as the capacity is generated by their transition. Electrochemistry, layered compounds, redox chemistry, sodium, transition metals. [Extracted from the article]